Improve IKAR reliability, security, and Android UX

.env.example

@@ -1 +1,8 @@
-IKAR_DATA_PATH=/media/myDrive/ikar-data
+IKAR_DATA_PATH=/mnt/data/ikar-data
+IKAR_BACKUP_PATH=/mnt/data/ikar-backups
+TURN_HOST=ikar.kusoft.xyz
+TURN_REALM=ikar.kusoft.xyz
+TURN_EXTERNAL_IP=195.216.241.165
+TURN_PRIVATE_IP=192.168.0.185
+TURN_USERNAME=ikar
+TURN_PASSWORD=replace-with-a-long-random-secret

Ikar.slnx

@@ -1,7 +1,6 @@
 <Solution>
   <Folder Name="/src/">
-    <Project Path="src/Ikar.Client/Ikar.Client.csproj" />
+    <Project Path="src/Ikar.Server.Tests/Ikar.Server.Tests.csproj" />
-    <Project Path="src/Ikar.CodexBridge/Ikar.CodexBridge.csproj" />
     <Project Path="src/Ikar.Server/Ikar.Server.csproj" />
     <Project Path="src/Ikar.Shared/Ikar.Shared.csproj" />
   </Folder>

IkarClassic.sln

@@ -9,13 +9,7 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.Shared", "src\Ikar.Sha
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.Server", "src\Ikar.Server\Ikar.Server.csproj", "{631B782D-44B2-4680-BC8C-1A0A948A1945}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.Client", "src\Ikar.Client\Ikar.Client.csproj", "{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}"
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.Server.Tests", "src\Ikar.Server.Tests\Ikar.Server.Tests.csproj", "{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.WinUI", "src\Ikar.WinUI\Ikar.WinUI.csproj", "{2900F762-FB89-44B7-AF69-D4908EEC50B2}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.CodexBridge", "src\Ikar.CodexBridge\Ikar.CodexBridge.csproj", "{57EC4F75-199D-4FFB-A658-D455AF1F41CF}"
-EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Ikar.CodexBridge.Tests", "src\Ikar.CodexBridge.Tests\Ikar.CodexBridge.Tests.csproj", "{318E90D6-56ED-491E-8454-22CB84B6FDD3}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -51,54 +45,18 @@ Global
 		{631B782D-44B2-4680-BC8C-1A0A948A1945}.Release|x64.Build.0 = Release|Any CPU
 		{631B782D-44B2-4680-BC8C-1A0A948A1945}.Release|x86.ActiveCfg = Release|Any CPU
 		{631B782D-44B2-4680-BC8C-1A0A948A1945}.Release|x86.Build.0 = Release|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Debug|x64.Build.0 = Debug|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Debug|x64.Build.0 = Debug|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Debug|x86.Build.0 = Debug|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Debug|x86.Build.0 = Debug|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Release|Any CPU.Build.0 = Release|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Release|Any CPU.Build.0 = Release|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Release|x64.ActiveCfg = Release|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Release|x64.ActiveCfg = Release|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Release|x64.Build.0 = Release|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Release|x64.Build.0 = Release|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Release|x86.ActiveCfg = Release|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Release|x86.ActiveCfg = Release|Any CPU
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60}.Release|x86.Build.0 = Release|Any CPU
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0}.Release|x86.Build.0 = Release|Any CPU
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Debug|Any CPU.ActiveCfg = Debug|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Debug|Any CPU.Build.0 = Debug|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Debug|x64.ActiveCfg = Debug|x64
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Debug|x64.Build.0 = Debug|x64
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Debug|x86.ActiveCfg = Debug|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Debug|x86.Build.0 = Debug|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Release|Any CPU.ActiveCfg = Release|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Release|Any CPU.Build.0 = Release|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Release|x64.ActiveCfg = Release|x64
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Release|x64.Build.0 = Release|x64
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Release|x86.ActiveCfg = Release|x86
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2}.Release|x86.Build.0 = Release|x86
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Debug|x64.Build.0 = Debug|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Debug|x86.Build.0 = Debug|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Release|Any CPU.Build.0 = Release|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Release|x64.ActiveCfg = Release|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Release|x64.Build.0 = Release|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Release|x86.ActiveCfg = Release|Any CPU
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF}.Release|x86.Build.0 = Release|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Debug|x64.ActiveCfg = Debug|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Debug|x64.Build.0 = Debug|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Debug|x86.ActiveCfg = Debug|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Debug|x86.Build.0 = Debug|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Release|Any CPU.Build.0 = Release|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Release|x64.ActiveCfg = Release|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Release|x64.Build.0 = Release|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Release|x86.ActiveCfg = Release|Any CPU
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -106,9 +64,6 @@ Global
 	GlobalSection(NestedProjects) = preSolution
 		{2FBB67AD-D250-4C69-AEA9-D0F7A18D623B} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
 		{631B782D-44B2-4680-BC8C-1A0A948A1945} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
-		{E5B4217E-FCA8-4944-99A6-12D07E7B5D60} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
+		{94F7D186-7CAA-4840-9C64-AC4792A1A6C0} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
-		{2900F762-FB89-44B7-AF69-D4908EEC50B2} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
-		{57EC4F75-199D-4FFB-A658-D455AF1F41CF} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
-		{318E90D6-56ED-491E-8454-22CB84B6FDD3} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
 	EndGlobalSection
 EndGlobal

docker-compose.rpi5.yml

@@ -7,9 +7,57 @@ services:
       context: .
       dockerfile: Dockerfile.server
     restart: unless-stopped
+    stop_grace_period: 30s
+    user: "${IKAR_UID:-1000}:${IKAR_GID:-1000}"
     env_file:
       - .env.server
     ports:
       - "127.0.0.1:5099:5099"
     volumes:
       - ${IKAR_DATA_PATH:?IKAR_DATA_PATH must be set in .env}:/app/Data
+      - ${IKAR_BACKUP_PATH:-/mnt/data/ikar-backups}:/backups:ro
+    environment:
+      Backup__Directory: /backups
+      Backup__RequireFreshBackup: "true"
+      WebRtc__IceServers__0__Urls__0: stun:stun.l.google.com:19302
+      WebRtc__IceServers__1__Urls__0: turn:${TURN_HOST:-ikar.kusoft.xyz}:3478?transport=udp
+      WebRtc__IceServers__1__Urls__1: turn:${TURN_HOST:-ikar.kusoft.xyz}:3478?transport=tcp
+      WebRtc__IceServers__1__Username: ${TURN_USERNAME:?TURN_USERNAME must be set in .env}
+      WebRtc__IceServers__1__Credential: ${TURN_PASSWORD:?TURN_PASSWORD must be set in .env}
+    logging:
+      driver: json-file
+      options:
+        max-size: "10m"
+        max-file: "3"
+    mem_limit: 768m
+    cpus: 2.0
+
+  ikar-turn:
+    container_name: ikar-turn
+    image: coturn/coturn:4.14.0-r0
+    platform: linux/arm64
+    restart: unless-stopped
+    network_mode: host
+    command:
+      - --no-cli
+      - --fingerprint
+      - --lt-cred-mech
+      - --realm=${TURN_REALM:-ikar.kusoft.xyz}
+      - --user=${TURN_USERNAME:?TURN_USERNAME must be set in .env}:${TURN_PASSWORD:?TURN_PASSWORD must be set in .env}
+      - --listening-ip=${TURN_PRIVATE_IP:?TURN_PRIVATE_IP must be set in .env}
+      - --relay-ip=${TURN_PRIVATE_IP:?TURN_PRIVATE_IP must be set in .env}
+      - --external-ip=${TURN_EXTERNAL_IP:?TURN_EXTERNAL_IP must be set in .env}/${TURN_PRIVATE_IP:?TURN_PRIVATE_IP must be set in .env}
+      - --listening-port=3478
+      - --min-port=49160
+      - --max-port=49200
+      - --no-tls
+      - --no-dtls
+      - --no-multicast-peers
+      - --log-file=stdout
+    logging:
+      driver: json-file
+      options:
+        max-size: "10m"
+        max-file: "3"
+    mem_limit: 256m
+    cpus: 1.0

scripts/backup-ikar-data.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+data_dir="${IKAR_DATA_PATH:-/mnt/data/ikar-data}"
+backup_dir="${IKAR_BACKUP_PATH:-/mnt/data/ikar-backups}"
+retention_days="${IKAR_BACKUP_RETENTION_DAYS:-14}"
+timestamp="$(date -u +%Y%m%dT%H%M%SZ)"
+work_dir="${backup_dir}/.ikar-${timestamp}.tmp"
+archive="${backup_dir}/ikar-${timestamp}.tar.gz"
+
+test -f "${data_dir}/ikar.db"
+mkdir -p "${backup_dir}"
+rm -rf "${work_dir}"
+mkdir -p "${work_dir}/Data"
+
+sqlite3 "${data_dir}/ikar.db" ".timeout 10000" ".backup '${work_dir}/Data/ikar.db'"
+test "$(sqlite3 "${work_dir}/Data/ikar.db" 'PRAGMA integrity_check;')" = "ok"
+
+for directory in Attachments AppUpdates secrets; do
+    if test -d "${data_dir}/${directory}"; then
+        rsync -a "${data_dir}/${directory}/" "${work_dir}/Data/${directory}/"
+    fi
+done
+
+tar -C "${work_dir}" -czf "${archive}.partial" Data
+gzip -t "${archive}.partial"
+mv "${archive}.partial" "${archive}"
+sha256sum "${archive}" > "${archive}.sha256"
+rm -rf "${work_dir}"
+
+find "${backup_dir}" -maxdepth 1 -type f -name 'ikar-*.tar.gz' -mtime "+${retention_days}" -delete
+find "${backup_dir}" -maxdepth 1 -type f -name 'ikar-*.tar.gz.sha256' -mtime "+${retention_days}" -delete
+
+printf '%s\n' "${archive}"

scripts/restore-ikar-data.sh

@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+verify_only=false
+if test "$#" -eq 2 && test "$2" = "--verify-only"; then
+    archive="$1"
+    staging_dir="$(mktemp -d "$(dirname "${archive}")/.ikar-verify-XXXXXX")"
+    verify_only=true
+elif test "$#" -eq 3 && test "$3" = "--confirm-restore"; then
+    archive="$1"
+    target_dir="$2"
+    mkdir -p "$(dirname "${target_dir}")"
+    staging_dir="$(mktemp -d "${target_dir}.restore-XXXXXX")"
+else
+    echo "Usage: $0 <backup.tar.gz> --verify-only" >&2
+    echo "   or: $0 <backup.tar.gz> <target-data-dir> --confirm-restore" >&2
+    exit 64
+fi
+
+cleanup() {
+    rm -rf -- "${staging_dir}"
+}
+trap cleanup EXIT
+
+test -f "${archive}"
+test -f "${archive}.sha256"
+(cd "$(dirname "${archive}")" && sha256sum -c "$(basename "${archive}.sha256")")
+tar -C "${staging_dir}" -xzf "${archive}"
+test -f "${staging_dir}/Data/ikar.db"
+test "$(sqlite3 "${staging_dir}/Data/ikar.db" 'PRAGMA integrity_check;')" = "ok"
+
+if test "${verify_only}" = true; then
+    echo "Backup verification completed successfully."
+    exit 0
+fi
+
+if test -e "${target_dir}"; then
+    mv "${target_dir}" "${target_dir}.before-restore-$(date -u +%Y%m%dT%H%M%SZ)"
+fi
+mv "${staging_dir}/Data" "${target_dir}"
+rmdir "${staging_dir}"
+trap - EXIT
+
+echo "Restore completed. Start the Ikar server and verify /health before removing the pre-restore directory."

src/Ikar.AndroidKotlin/app/build.gradle.kts

@@ -37,8 +37,8 @@ android {
         applicationId = "com.seven.ikar.kotlin"
         minSdk = 24
         targetSdk = 36
-        versionCode = 209
+        versionCode = 211
-        versionName = "3.96"
+        versionName = "3.98"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
         vectorDrawables.useSupportLibrary = true
@@ -57,7 +57,8 @@ android {
 
     buildTypes {
         release {
-            isMinifyEnabled = false
+            isMinifyEnabled = true
+            isShrinkResources = true
             proguardFiles(
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
@@ -123,4 +124,5 @@ dependencies {
     implementation("androidx.compose.material:material-icons-extended")
     debugImplementation("androidx.compose.ui:ui-tooling")
     debugImplementation("androidx.compose.ui:ui-test-manifest")
+    testImplementation("junit:junit:4.13.2")
 }

src/Ikar.AndroidKotlin/app/proguard-rules.pro

@@ -1 +1,17 @@
-# Intentionally empty for the first migration pass.
+# SignalR creates its wire DTOs through reflection.
+-keep class com.seven.ikar.kotlin.core.realtime.** { *; }
+
+# Firebase and WorkManager instantiate these Android components by class name.
+-keep class com.seven.ikar.kotlin.core.push.IkarFirebaseMessagingService { *; }
+-keep class com.seven.ikar.kotlin.feature.transfer.**Worker { public <init>(...); }
+
+# Keep Kotlin serialization-generated serializers and their companions.
+-keepclassmembers class com.seven.ikar.kotlin.core.model.** {
+    *** Companion;
+}
+-keepclasseswithmembers,includedescriptorclasses class * {
+    kotlinx.serialization.KSerializer serializer(...);
+}
+
+# SLF4J uses this optional binding only when an implementation is packaged.
+-dontwarn org.slf4j.impl.StaticLoggerBinder

src/Ikar.AndroidKotlin/app/src/main/AndroidManifest.xml

@@ -16,9 +16,10 @@
 
     <application
         android:name=".app.IkarNativeApp"
-        android:allowBackup="true"
+        android:allowBackup="false"
+        android:fullBackupContent="false"
         android:icon="@drawable/appicon"
-        android:label="Икар"
+        android:label="@string/app_name"
         android:roundIcon="@drawable/appicon"
         android:supportsRtl="true"
         android:theme="@android:style/Theme.Material.Light.NoActionBar">

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/app/AppContainer.kt

@@ -61,7 +61,7 @@ class AppContainer(context: Context) {
     }
 
     private val loggingInterceptor = HttpLoggingInterceptor().apply {
-        level = HttpLoggingInterceptor.Level.BASIC
+        level = if (BuildConfig.DEBUG) HttpLoggingInterceptor.Level.BASIC else HttpLoggingInterceptor.Level.NONE
     }
 
     val pushSettings = AndroidPushSettings(appContext)

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/local/IkarLocalDatabase.kt

@@ -9,7 +9,7 @@ import androidx.sqlite.db.SupportSQLiteDatabase
 
 @Database(
     entities = [CachedChatMessageEntity::class, CachedChatEntity::class, TransferQueueEntity::class],
-    version = 4,
+    version = 5,
     exportSchema = false
 )
 abstract class IkarLocalDatabase : RoomDatabase() {
@@ -79,6 +79,12 @@ abstract class IkarLocalDatabase : RoomDatabase() {
             }
         }
 
+        private val Migration4To5 = object : Migration(4, 5) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL("ALTER TABLE transfer_queue ADD COLUMN clientMessageId TEXT")
+            }
+        }
+
         fun getInstance(context: Context): IkarLocalDatabase =
             instance ?: synchronized(this) {
                 instance ?: Room.databaseBuilder(
@@ -86,7 +92,7 @@ abstract class IkarLocalDatabase : RoomDatabase() {
                     IkarLocalDatabase::class.java,
                     "ikar-local.db"
                 )
-                    .addMigrations(Migration1To2, Migration2To3, Migration3To4)
+                    .addMigrations(Migration1To2, Migration2To3, Migration3To4, Migration4To5)
                     .build()
                     .also { instance = it }
             }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/local/TransferQueueEntity.kt

@@ -17,6 +17,7 @@ data class TransferQueueEntity(
     val chatId: String?,
     val text: String?,
     val replyToMessageId: String?,
+    val clientMessageId: String?,
     val attachmentId: String?,
     val storyVisibility: String?,
     val hasProtectedContent: Boolean,
@@ -40,6 +41,12 @@ interface TransferQueueDao {
     @Query("SELECT * FROM transfer_queue WHERE groupId = :groupId ORDER BY sortOrder ASC")
     suspend fun getGroup(groupId: String): List<TransferQueueEntity>
 
+    @Query("SELECT * FROM transfer_queue WHERE groupId = :groupId ORDER BY sortOrder ASC")
+    fun observeGroup(groupId: String): Flow<List<TransferQueueEntity>>
+
+    @Query("SELECT groupId FROM transfer_queue WHERE attachmentId = :attachmentId AND type = 'download' AND status IN ('queued', 'running') ORDER BY createdAtMillis DESC LIMIT 1")
+    suspend fun findActiveDownloadGroup(attachmentId: String): String?
+
     @Query("SELECT * FROM transfer_queue WHERE chatId = :chatId AND status IN ('queued', 'running', 'failed') ORDER BY createdAtMillis ASC, sortOrder ASC")
     fun observeActiveForChat(chatId: String): Flow<List<TransferQueueEntity>>
 
@@ -60,6 +67,7 @@ interface TransferQueueDao {
 }
 
 object TransferQueueTypes {
+    const val TextMessage = "text_message"
     const val Upload = "upload"
     const val StoryUpload = "story_upload"
     const val Download = "download"

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/model/ClientMessageIds.kt

@@ -0,0 +1,16 @@
+package com.seven.ikar.kotlin.core.model
+
+import java.util.UUID
+
+object ClientMessageIds {
+    const val LocalPrefix = "local-"
+
+    fun newClientId(): String = UUID.randomUUID().toString()
+
+    fun localId(clientMessageId: String): String = "$LocalPrefix$clientMessageId"
+
+    fun clientIdFromLocalId(localMessageId: String): String? =
+        localMessageId.takeIf { it.startsWith(LocalPrefix) }
+            ?.removePrefix(LocalPrefix)
+            ?.takeIf(String::isNotBlank)
+}

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/model/Models.kt

@@ -252,7 +252,8 @@ data class MessageDto(
     val viewCount: Int? = null,
     val storyReply: StoryReplyDto? = null,
     val discussionMessageId: String? = null,
-    val commentCount: Int? = null
+    val commentCount: Int? = null,
+    val clientMessageId: String? = null
 )
 
 @Serializable
@@ -608,7 +609,8 @@ data class SendMessageRequest(
     val topicId: String? = null,
     val hasProtectedContent: Boolean? = null,
     val ttlSeconds: Int? = null,
-    val storyReplyStoryId: String? = null
+    val storyReplyStoryId: String? = null,
+    val clientMessageId: String? = null
 )
 
 @Serializable

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/network/ApiClient.kt

@@ -648,7 +648,8 @@ class ApiClient(
         topicId: String? = null,
         hasProtectedContent: Boolean? = null,
         ttlSeconds: Int? = null,
-        storyReplyStoryId: String? = null
+        storyReplyStoryId: String? = null,
+        clientMessageId: String? = null
     ): MessageDto =
         executeJsonRequest(
             Request.Builder()
@@ -662,7 +663,8 @@ class ApiClient(
                             topicId = topicId,
                             hasProtectedContent = hasProtectedContent,
                             ttlSeconds = ttlSeconds,
-                            storyReplyStoryId = storyReplyStoryId
+                            storyReplyStoryId = storyReplyStoryId,
+                            clientMessageId = clientMessageId
                         )
                     ).toRequestBody(JSON)
                 )
@@ -886,10 +888,12 @@ class ApiClient(
                         ?: attachment.fileSizeBytes.takeIf { it >= 0L }
                         ?: -1L
                     targetFile.parentFile?.mkdirs()
+                    val partialFile = File(targetFile.parentFile ?: File("."), "${targetFile.name}.part")
+                    partialFile.delete()
+                    var bytesRead = 0L
                     body.byteStream().use { input ->
-                        targetFile.outputStream().use { output ->
+                        partialFile.outputStream().use { output ->
                             val buffer = ByteArray(DEFAULT_BUFFER_SIZE)
-                            var bytesRead = 0L
                             while (true) {
                                 val read = input.read(buffer)
                                 if (read < 0) {
@@ -900,9 +904,21 @@ class ApiClient(
                                 onProgress?.invoke(bytesRead, totalBytes)
                             }
                         }
+
+                        if (totalBytes > 0L && bytesRead != totalBytes) {
+                            throw IOException("Incomplete attachment download.")
+                        }
                     }
 
-            DownloadedAttachmentFile(
+                    if (targetFile.exists() && !targetFile.delete()) {
+                        throw IOException("Could not replace cached attachment.")
+                    }
+                    if (!partialFile.renameTo(targetFile)) {
+                        partialFile.copyTo(targetFile, overwrite = true)
+                        partialFile.delete()
+                    }
+
+                    DownloadedAttachmentFile(
                         fileName = attachment.fileName,
                         contentType = body.contentType()?.toString()
                             ?: response.header("Content-Type")
@@ -912,6 +928,8 @@ class ApiClient(
                     )
                 }
             } catch (error: IOException) {
+                val partialFile = File(targetFile.parentFile ?: File("."), "${targetFile.name}.part")
+                partialFile.delete()
                 throw ApiException(-1, networkErrorMessage())
             }
         }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/push/NotificationActionReceiver.kt

@@ -3,10 +3,12 @@ package com.seven.ikar.kotlin.core.push
 import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
+import androidx.core.app.RemoteInput
 import com.seven.ikar.kotlin.app.IkarNativeApp
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
+import java.util.UUID
 
 class NotificationActionReceiver : BroadcastReceiver() {
     override fun onReceive(context: Context, intent: Intent) {
@@ -24,11 +26,42 @@ class NotificationActionReceiver : BroadcastReceiver() {
         val action = intent.action.orEmpty()
         when (action) {
             NotificationAction.MarkReadAction -> handleMarkRead(context, intent)
+            NotificationAction.InlineReplyAction -> handleInlineReply(context, intent)
             NotificationAction.AcceptIncomingCallAction -> handleAcceptIncomingCall(context, intent)
             NotificationAction.DeclineIncomingCallAction -> handleDeclineIncomingCall(context, intent)
         }
     }
 
+    private suspend fun handleInlineReply(context: Context, intent: Intent) {
+        val chatId = intent.getStringExtra(PushDataKeys.ChatId).orEmpty()
+        val notificationId = intent.getIntExtra(NotificationAction.NotificationIdExtra, Int.MIN_VALUE)
+        val text = RemoteInput.getResultsFromIntent(intent)
+            ?.getCharSequence(NotificationAction.InlineReplyResultKey)
+            ?.toString()
+            ?.trim()
+            .orEmpty()
+        if (chatId.isBlank() || text.isBlank()) {
+            return
+        }
+
+        val app = context.applicationContext as? IkarNativeApp ?: return
+        runCatching {
+            app.container.executeAuthorized { session ->
+                app.container.apiClient.sendMessage(
+                    chatId = chatId,
+                    text = text,
+                    accessToken = session.accessToken,
+                    clientMessageId = UUID.randomUUID().toString()
+                )
+            }
+        }.onSuccess {
+            app.container.realtimeService.notifyChatsChangedLocally()
+            if (notificationId != Int.MIN_VALUE) {
+                ChatNotificationDismissalManager.cancelNotification(context, chatId, notificationId)
+            }
+        }
+    }
+
     private suspend fun handleMarkRead(context: Context, intent: Intent) {
         val chatId = intent.getStringExtra(PushDataKeys.ChatId).orEmpty()
         val messageId = intent.getStringExtra(PushDataKeys.MessageId).orEmpty()
@@ -92,7 +125,9 @@ class NotificationActionReceiver : BroadcastReceiver() {
 
 object NotificationAction {
     const val MarkReadAction = "com.seven.ikar.kotlin.NOTIFICATION_MARK_READ"
+    const val InlineReplyAction = "com.seven.ikar.kotlin.NOTIFICATION_INLINE_REPLY"
     const val AcceptIncomingCallAction = "com.seven.ikar.kotlin.NOTIFICATION_ACCEPT_INCOMING_CALL"
     const val DeclineIncomingCallAction = "com.seven.ikar.kotlin.NOTIFICATION_DECLINE_INCOMING_CALL"
     const val NotificationIdExtra = "notificationId"
+    const val InlineReplyResultKey = "inlineReplyText"
 }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/push/PushNotificationDisplayService.kt

@@ -11,6 +11,7 @@ import android.os.Vibrator
 import android.os.VibratorManager
 import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
+import androidx.core.app.RemoteInput
 import androidx.core.content.ContextCompat
 import com.seven.ikar.kotlin.BuildConfig
 import com.seven.ikar.kotlin.MainActivity
@@ -218,11 +219,20 @@ object PushNotificationDisplayService {
         }
 
         val pendingIntent = PendingIntent.getActivity(context, notificationId, intent, flags)
-        val replyPendingIntent = PendingIntent.getActivity(
+        val replyFlags = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_MUTABLE
+        } else {
+            PendingIntent.FLAG_UPDATE_CURRENT
+        }
+        val replyPendingIntent = PendingIntent.getBroadcast(
             context,
             notificationId + 1,
-            intent,
+            Intent(context, NotificationActionReceiver::class.java).apply {
-            flags
+                action = NotificationAction.InlineReplyAction
+                putExtra(PushDataKeys.ChatId, data[PushDataKeys.ChatId])
+                putExtra(NotificationAction.NotificationIdExtra, notificationId)
+            },
+            replyFlags
         )
         val markReadPendingIntent = PendingIntent.getBroadcast(
             context,
@@ -292,8 +302,19 @@ object PushNotificationDisplayService {
             !data[PushDataKeys.ChatId].isNullOrBlank() &&
             !data[PushDataKeys.MessageId].isNullOrBlank()
         ) {
+            val remoteInput = RemoteInput.Builder(NotificationAction.InlineReplyResultKey)
+                .setLabel("Ответ")
+                .build()
+            val replyAction = NotificationCompat.Action.Builder(
+                android.R.drawable.ic_menu_send,
+                "Ответить",
+                replyPendingIntent
+            )
+                .addRemoteInput(remoteInput)
+                .setAllowGeneratedReplies(true)
+                .build()
             notificationBuilder
-                .addAction(android.R.drawable.ic_menu_send, "Ответить", replyPendingIntent)
+                .addAction(replyAction)
                 .addAction(android.R.drawable.ic_menu_view, "Отметить как прочитанное", markReadPendingIntent)
         }
 

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/realtime/RealtimeService.kt

@@ -53,6 +53,9 @@ class RealtimeService(
     private val _stage = MutableStateFlow(RealtimeConnectionStage.Disconnected)
     val stage: StateFlow<RealtimeConnectionStage> = _stage
 
+    private val _connectionRestored = MutableSharedFlow<Unit>(extraBufferCapacity = 1)
+    val connectionRestored: SharedFlow<Unit> = _connectionRestored
+
     private val _messagesCreated = MutableSharedFlow<MessageDto>(extraBufferCapacity = 32)
     val messagesCreated: SharedFlow<MessageDto> = _messagesCreated
 
@@ -209,6 +212,7 @@ class RealtimeService(
                 newConnection.start().blockingAwait()
             }.onSuccess {
                 _stage.value = RealtimeConnectionStage.Connected
+                _connectionRestored.tryEmit(Unit)
             }.onFailure {
                 if (connection == newConnection) {
                     connection = null

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/security/AndroidKeystoreCipher.kt

@@ -0,0 +1,61 @@
+package com.seven.ikar.kotlin.core.security
+
+import android.security.keystore.KeyGenParameterSpec
+import android.security.keystore.KeyProperties
+import android.util.Base64
+import java.security.KeyStore
+import javax.crypto.Cipher
+import javax.crypto.KeyGenerator
+import javax.crypto.SecretKey
+import javax.crypto.spec.GCMParameterSpec
+
+class AndroidKeystoreCipher(private val keyAlias: String) {
+    fun encrypt(value: String): String {
+        val cipher = Cipher.getInstance(Transformation)
+        cipher.init(Cipher.ENCRYPT_MODE, loadOrCreateKey())
+        val encrypted = cipher.doFinal(value.toByteArray(Charsets.UTF_8))
+        return listOf(
+            Version,
+            Base64.encodeToString(cipher.iv, Base64.NO_WRAP),
+            Base64.encodeToString(encrypted, Base64.NO_WRAP)
+        ).joinToString(Separator)
+    }
+
+    fun decrypt(value: String): String? = runCatching {
+        val parts = value.split(Separator, limit = 3)
+        require(parts.size == 3 && parts[0] == Version)
+        val iv = Base64.decode(parts[1], Base64.NO_WRAP)
+        val encrypted = Base64.decode(parts[2], Base64.NO_WRAP)
+        val cipher = Cipher.getInstance(Transformation)
+        cipher.init(Cipher.DECRYPT_MODE, loadOrCreateKey(), GCMParameterSpec(GcmTagBits, iv))
+        cipher.doFinal(encrypted).toString(Charsets.UTF_8)
+    }.getOrNull()
+
+    private fun loadOrCreateKey(): SecretKey {
+        val keyStore = KeyStore.getInstance(AndroidKeyStore).apply { load(null) }
+        (keyStore.getKey(keyAlias, null) as? SecretKey)?.let { return it }
+
+        return KeyGenerator.getInstance(KeyProperties.KEY_ALGORITHM_AES, AndroidKeyStore).run {
+            init(
+                KeyGenParameterSpec.Builder(
+                    keyAlias,
+                    KeyProperties.PURPOSE_ENCRYPT or KeyProperties.PURPOSE_DECRYPT
+                )
+                    .setBlockModes(KeyProperties.BLOCK_MODE_GCM)
+                    .setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_NONE)
+                    .setRandomizedEncryptionRequired(true)
+                    .setKeySize(256)
+                    .build()
+            )
+            generateKey()
+        }
+    }
+
+    private companion object {
+        const val AndroidKeyStore = "AndroidKeyStore"
+        const val Transformation = "AES/GCM/NoPadding"
+        const val GcmTagBits = 128
+        const val Version = "v1"
+        const val Separator = ":"
+    }
+}

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/session/SessionStore.kt

@@ -3,28 +3,53 @@ package com.seven.ikar.kotlin.core.session
 import android.content.Context
 import android.content.SharedPreferences
 import com.seven.ikar.kotlin.core.model.AuthSessionDto
+import com.seven.ikar.kotlin.core.security.AndroidKeystoreCipher
 import kotlinx.serialization.json.Json
 
 class SessionStore(context: Context, private val json: Json) {
     private val preferences: SharedPreferences =
         context.getSharedPreferences("ikar_kotlin_session", Context.MODE_PRIVATE)
+    private val cipher = AndroidKeystoreCipher("ikar.session.v1")
 
     fun read(): AuthSessionDto? {
-        val raw = preferences.getString(KEY_SESSION, null) ?: return null
+        val encrypted = preferences.getString(KEY_ENCRYPTED_SESSION, null)
-        return runCatching { json.decodeFromString<AuthSessionDto>(raw) }.getOrNull()
+        if (encrypted != null) {
+            val raw = cipher.decrypt(encrypted) ?: run {
+                clear()
+                return null
+            }
+            return decode(raw)
+        }
+
+        val legacy = preferences.getString(KEY_LEGACY_SESSION, null) ?: return null
+        val session = decode(legacy) ?: run {
+            clear()
+            return null
+        }
+        save(session)
+        return session
     }
 
     fun save(session: AuthSessionDto) {
+        val encrypted = cipher.encrypt(json.encodeToString(AuthSessionDto.serializer(), session))
         preferences.edit()
-            .putString(KEY_SESSION, json.encodeToString(AuthSessionDto.serializer(), session))
+            .putString(KEY_ENCRYPTED_SESSION, encrypted)
-            .apply()
+            .remove(KEY_LEGACY_SESSION)
+            .commit()
     }
 
     fun clear() {
-        preferences.edit().remove(KEY_SESSION).apply()
+        preferences.edit()
+            .remove(KEY_ENCRYPTED_SESSION)
+            .remove(KEY_LEGACY_SESSION)
+            .commit()
     }
 
+    private fun decode(raw: String): AuthSessionDto? =
+        runCatching { json.decodeFromString<AuthSessionDto>(raw) }.getOrNull()
+
     companion object {
-        private const val KEY_SESSION = "session"
+        private const val KEY_ENCRYPTED_SESSION = "encrypted_session"
+        private const val KEY_LEGACY_SESSION = "session"
     }
 }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/core/settings/AndroidAppSettings.kt

@@ -1,6 +1,7 @@
 package com.seven.ikar.kotlin.core.settings
 
 import android.content.Context
+import com.seven.ikar.kotlin.core.security.AndroidKeystoreCipher
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
@@ -46,6 +47,7 @@ data class AppSettingsSnapshot(
 
 class AndroidAppSettings(context: Context) {
     private val preferences = context.getSharedPreferences(PREFERENCES_NAME, Context.MODE_PRIVATE)
+    private val secretCipher = AndroidKeystoreCipher("ikar.settings.v1")
     private val _snapshot = MutableStateFlow(loadSnapshot())
     val snapshot: StateFlow<AppSettingsSnapshot> = _snapshot.asStateFlow()
 
@@ -68,7 +70,7 @@ class AndroidAppSettings(context: Context) {
             proxyType = getEnum(KEY_PROXY_TYPE, AppProxyType.Socks5).supportedProxyType(),
             proxyHost = preferences.getString(KEY_PROXY_HOST, "").orEmpty(),
             proxyPort = preferences.getInt(KEY_PROXY_PORT, 1080).coerceIn(1, 65_535),
-            proxySecret = preferences.getString(KEY_PROXY_SECRET, "").orEmpty()
+            proxySecret = readProxySecret()
         )
 
     fun update(transform: (AppSettingsSnapshot) -> AppSettingsSnapshot) {
@@ -99,7 +101,11 @@ class AndroidAppSettings(context: Context) {
             putString(KEY_PROXY_TYPE, sanitized.proxyType.name)
             putString(KEY_PROXY_HOST, sanitized.proxyHost)
             putInt(KEY_PROXY_PORT, sanitized.proxyPort)
-            putString(KEY_PROXY_SECRET, sanitized.proxySecret)
+            putString(
+                KEY_ENCRYPTED_PROXY_SECRET,
+                sanitized.proxySecret.takeIf(String::isNotEmpty)?.let(secretCipher::encrypt)
+            )
+            remove(KEY_PROXY_SECRET)
             apply()
         }
         _snapshot.value = sanitized
@@ -117,6 +123,22 @@ class AndroidAppSettings(context: Context) {
             ?: defaultValue
     }
 
+    private fun readProxySecret(): String {
+        val encrypted = preferences.getString(KEY_ENCRYPTED_PROXY_SECRET, null)
+        if (encrypted != null) {
+            return secretCipher.decrypt(encrypted).orEmpty()
+        }
+
+        val legacy = preferences.getString(KEY_PROXY_SECRET, "").orEmpty()
+        if (legacy.isNotEmpty()) {
+            preferences.edit()
+                .putString(KEY_ENCRYPTED_PROXY_SECRET, secretCipher.encrypt(legacy))
+                .remove(KEY_PROXY_SECRET)
+                .commit()
+        }
+        return legacy
+    }
+
     private fun AppProxyType.supportedProxyType(): AppProxyType = when (this) {
         AppProxyType.MtProto -> AppProxyType.Socks5
         else -> this
@@ -141,5 +163,6 @@ class AndroidAppSettings(context: Context) {
         private const val KEY_PROXY_HOST = "proxy_host"
         private const val KEY_PROXY_PORT = "proxy_port"
         private const val KEY_PROXY_SECRET = "proxy_secret"
+        private const val KEY_ENCRYPTED_PROXY_SECRET = "encrypted_proxy_secret"
     }
 }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/chat/ChatScreen.kt

@@ -25,6 +25,7 @@ import androidx.compose.foundation.gestures.detectTapGestures
 import androidx.compose.foundation.gestures.detectTransformGestures
 import androidx.compose.foundation.horizontalScroll
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.aspectRatio
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.foundation.layout.Column
@@ -3681,20 +3682,73 @@ private fun InlineMessageImage(
     onClick: () -> Unit,
     onLongPress: () -> Unit
 ) {
-    AuthenticatedAsyncImage(
+    ChatPhotoImage(
         imageUrl = imageUrl,
         accessToken = "",
         contentDescription = "",
-        modifier = Modifier
+        onClick = onClick,
-            .fillMaxWidth()
+        onLongPress = onLongPress
-            .heightIn(min = 120.dp, max = 420.dp)
-            .clip(RoundedCornerShape(16.dp))
-            .combinedClickable(onClick = onClick, onLongClick = onLongPress)
-            .background(Color(0xFFF7FAFD)),
-        contentScale = ContentScale.Fit
     )
 }
 
+@OptIn(ExperimentalFoundationApi::class)
+@Composable
+private fun ChatPhotoImage(
+    imageUrl: String?,
+    accessToken: String?,
+    contentDescription: String,
+    modifier: Modifier = Modifier,
+    onClick: () -> Unit,
+    onLongPress: () -> Unit
+) {
+    var imageAspectRatio by remember(imageUrl) { mutableStateOf<Float?>(null) }
+
+    BoxWithConstraints(
+        modifier = modifier.fillMaxWidth(),
+        contentAlignment = Alignment.Center
+    ) {
+        val maxPhotoHeight = 420.dp
+        val knownRatio = imageAspectRatio
+        val imageModifier = if (knownRatio != null) {
+            val safeRatio = knownRatio.coerceIn(0.12f, 8f)
+            val targetWidth = if (maxWidth / safeRatio > maxPhotoHeight) {
+                maxPhotoHeight * safeRatio
+            } else {
+                maxWidth
+            }
+            Modifier
+                .width(targetWidth)
+                .aspectRatio(safeRatio)
+        } else {
+            Modifier
+                .fillMaxWidth()
+                .height(220.dp)
+        }
+
+        Box(
+            modifier = imageModifier
+                .clip(RoundedCornerShape(16.dp))
+                .combinedClickable(onClick = onClick, onLongClick = onLongPress)
+        ) {
+            AuthenticatedAsyncImage(
+                imageUrl = imageUrl,
+                accessToken = accessToken,
+                contentDescription = contentDescription,
+                modifier = Modifier.fillMaxSize(),
+                contentScale = ContentScale.Crop,
+                onSuccess = { state ->
+                    val drawable = state.result.drawable
+                    val intrinsicWidth = drawable.intrinsicWidth
+                    val intrinsicHeight = drawable.intrinsicHeight
+                    if (intrinsicWidth > 0 && intrinsicHeight > 0) {
+                        imageAspectRatio = intrinsicWidth.toFloat() / intrinsicHeight.toFloat()
+                    }
+                }
+            )
+        }
+    }
+}
+
 @OptIn(ExperimentalFoundationApi::class)
 @Composable
 private fun InlineMessageAudio(
@@ -3888,17 +3942,12 @@ private fun AttachmentCard(
 ) {
     when {
         attachment.isImageAttachment() -> {
-            AuthenticatedAsyncImage(
+            ChatPhotoImage(
                 imageUrl = attachmentUrl,
                 accessToken = accessToken,
                 contentDescription = attachment.fileName,
-                modifier = Modifier
+                onClick = onClick,
-                    .fillMaxWidth()
+                onLongPress = onLongPress
-                    .heightIn(min = 120.dp, max = 420.dp)
-                    .clip(RoundedCornerShape(16.dp))
-                    .combinedClickable(onClick = onClick, onLongClick = onLongPress)
-                    .background(Color(0xFFF7FAFD)),
-                contentScale = ContentScale.Fit
             )
         }
 

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/chat/ChatViewModel.kt

@@ -18,6 +18,7 @@ import com.seven.ikar.kotlin.core.model.BotCommandDto
 import com.seven.ikar.kotlin.core.model.CallMediaType
 import com.seven.ikar.kotlin.core.model.ChatDetailsDto
 import com.seven.ikar.kotlin.core.model.ChatType
+import com.seven.ikar.kotlin.core.model.ClientMessageIds
 import com.seven.ikar.kotlin.core.model.MessageDeliveryState
 import com.seven.ikar.kotlin.core.model.MessageDto
 import com.seven.ikar.kotlin.core.model.MessageReplyDto
@@ -26,6 +27,8 @@ import com.seven.ikar.kotlin.core.model.UserSummaryDto
 import com.seven.ikar.kotlin.core.network.ServerConfig
 import com.seven.ikar.kotlin.core.network.UploadFileSource
 import com.seven.ikar.kotlin.core.local.TransferQueueEntity
+import com.seven.ikar.kotlin.core.local.TransferQueueStatus
+import com.seven.ikar.kotlin.core.local.TransferQueueTypes
 import com.seven.ikar.kotlin.feature.call.AudioCallSnapshot
 import com.seven.ikar.kotlin.feature.call.AudioCallStage
 import com.seven.ikar.kotlin.feature.transfer.TransferForegroundNotification
@@ -164,7 +167,6 @@ private val DefaultCodexBridgeBotCommands = listOf(
 
 private val BotThreadOptionRegex = Regex("""^(?<index>\d+)\.\s+(?<title>.+?)(?<selected>\s+\[выбран])?$""")
 private val ChatTimestampFormatter: DateTimeFormatter = DateTimeFormatter.ofPattern("HH:mm", Locale("ru", "RU"))
-private const val LocalMessageIdPrefix = "local-"
 
 class ChatViewModel(
     private val container: AppContainer,
@@ -703,14 +705,14 @@ class ChatViewModel(
                     }
 
                     draftText.isNotBlank() -> {
-                        container.executeAuthorized { session ->
+                        val clientMessageId = optimisticMessage?.clientMessageId ?: UUID.randomUUID().toString()
-                            container.apiClient.sendMessage(
+                        container.transferQueueRepository.enqueueTextMessage(
-                                chatId = chatId,
+                            chatId = chatId,
-                                text = draftText,
+                            text = draftText,
-                                accessToken = session.accessToken,
+                            replyToMessageId = replyToMessageId,
-                                replyToMessageId = replyToMessageId
+                            clientMessageId = clientMessageId
-                            )
+                        )
-                        }
+                        null
                     }
 
                     else -> null
@@ -1315,10 +1317,10 @@ class ChatViewModel(
         val cachedFile = cachedAttachmentFiles[attachment.id]
             ?.localPath
             ?.let(::File)
-            ?.takeIf { it.exists() }
+            ?.takeIf { it.isCompleteCacheFileFor(attachment) }
             ?: container.attachmentFileService
                 .createAttachmentCacheFile(attachment.id, attachment.fileName)
-                .takeIf { it.exists() }
+                .takeIf { it.isCompleteCacheFileFor(attachment) }
                 ?.also { file ->
                     cachedAttachmentFiles[attachment.id] = LocalAttachmentFile(
                         fileName = attachment.fileName,
@@ -1419,8 +1421,9 @@ class ChatViewModel(
 
     private fun buildOptimisticMessage(state: ChatUiState, text: String): MessageDto? {
         val session = state.session ?: container.sessionStore.read() ?: return null
+        val clientMessageId = ClientMessageIds.newClientId()
         return MessageDto(
-            id = "$LocalMessageIdPrefix${UUID.randomUUID()}",
+            id = ClientMessageIds.localId(clientMessageId),
             chatId = chatId,
             chatType = state.chatType,
             sender = session.user,
@@ -1431,13 +1434,17 @@ class ChatViewModel(
             replyTo = state.replyTo,
             postedAsChannel = state.chatType == ChatType.Channel,
             displayAuthorName = if (state.chatType == ChatType.Channel) state.title else session.user.displayName,
-            viewCount = if (state.chatType == ChatType.Channel) 0 else null
+            viewCount = if (state.chatType == ChatType.Channel) 0 else null,
+            clientMessageId = clientMessageId
         )
     }
 
     private fun applyChat(chat: ChatDetailsDto, session: AuthSessionDto) {
         val previousState = _uiState.value
-        val localMessages = previousState.messages.filter { it.isLocalMessage() }
+        val receivedClientMessageIds = chat.messages.mapNotNullTo(mutableSetOf(), MessageDto::clientMessageId)
+        val localMessages = previousState.messages.filter { message ->
+            message.isLocalMessage() && message.clientMessageId !in receivedClientMessageIds
+        }
         val orderedMessages = (chat.messages + localMessages)
             .distinctBy { it.id }
             .sortedBy { it.sentAt }
@@ -1530,6 +1537,11 @@ class ChatViewModel(
                 refresh()
             }
         }
+        viewModelScope.launch {
+            container.realtimeService.connectionRestored.collect {
+                refresh()
+            }
+        }
         viewModelScope.launch {
             container.realtimeService.typingChanged.collect(::handleTypingChanged)
         }
@@ -1659,7 +1671,25 @@ class ChatViewModel(
     private fun attachTransferQueueState() {
         viewModelScope.launch {
             container.transferQueueRepository.observeActiveForChat(chatId).collect { items ->
-                _uiState.value = _uiState.value.copy(activeTransfers = items.toTransferQueueUiState())
+                val currentState = _uiState.value
+                val textItems = items.filter { it.type == TransferQueueTypes.TextMessage }
+                val activeTextLocalIds = textItems.mapNotNullTo(mutableSetOf()) { item ->
+                    item.clientMessageId?.let(ClientMessageIds::localId)
+                }
+                val failedTextLocalIds = textItems
+                    .filter { it.status == TransferQueueStatus.Failed }
+                    .mapNotNullTo(mutableSetOf()) { item ->
+                        item.clientMessageId?.let(ClientMessageIds::localId)
+                    }
+                _uiState.value = currentState.copy(
+                    activeTransfers = items
+                        .filterNot { it.type == TransferQueueTypes.TextMessage }
+                        .toTransferQueueUiState(),
+                    sendingLocalMessageIds = currentState.sendingLocalMessageIds +
+                        (activeTextLocalIds - failedTextLocalIds),
+                    failedLocalMessageIds = (currentState.failedLocalMessageIds - activeTextLocalIds) +
+                        failedTextLocalIds
+                )
             }
         }
     }
@@ -1670,10 +1700,16 @@ class ChatViewModel(
     }
 
     private suspend fun ensureAttachmentDownloaded(attachment: AttachmentDto): LocalAttachmentFile {
-        cachedAttachmentFiles[attachment.id]?.let { return it }
+        cachedAttachmentFiles[attachment.id]
+            ?.takeIf { File(it.localPath).isCompleteCacheFileFor(attachment) }
+            ?.let { return it }
+            ?: cachedAttachmentFiles.remove(attachment.id)
 
         val target = container.attachmentFileService.createAttachmentCacheFile(attachment.id, attachment.fileName)
-        if (target.exists()) {
+        if (target.exists() && !target.isCompleteCacheFileFor(attachment)) {
+            target.delete()
+        }
+        if (target.isCompleteCacheFileFor(attachment)) {
             val cached = LocalAttachmentFile(
                 fileName = attachment.fileName,
                 contentType = attachment.contentType,
@@ -1686,8 +1722,20 @@ class ChatViewModel(
         }
 
         if (attachment.fileSizeBytes >= TransferForegroundNotification.LargeTransferThresholdBytes) {
-            container.transferQueueRepository.enqueueDownload(chatId, attachment)
+            val groupId = container.transferQueueRepository.enqueueDownload(chatId, attachment)
-            throw IllegalStateException("Large download queued. Try opening it again when the transfer completes.")
+            container.transferQueueRepository.awaitCompletion(groupId)
+            if (!target.isCompleteCacheFileFor(attachment)) {
+                throw IllegalStateException("Downloaded attachment is incomplete.")
+            }
+            return LocalAttachmentFile(
+                fileName = attachment.fileName,
+                contentType = attachment.contentType,
+                fileSizeBytes = target.length(),
+                localPath = target.absolutePath
+            ).also { cached ->
+                cachedAttachmentFiles[attachment.id] = cached
+                notifyAttachmentCacheChanged()
+            }
         }
 
         return container.executeAuthorized { session ->
@@ -1727,8 +1775,15 @@ class ChatViewModel(
             .filterNot { it.hasProtectedContent || it.isDeleted() }
             .flatMap { it.attachments.asSequence() }
             .filter { attachment -> shouldAutoDownload(attachment, settings, isUnmetered) }
-            .filterNot { attachment -> cachedAttachmentFiles.containsKey(attachment.id) }
+            .filterNot { attachment ->
-            .filterNot { attachment -> container.attachmentFileService.createAttachmentCacheFile(attachment.id, attachment.fileName).exists() }
+                cachedAttachmentFiles[attachment.id]
+                    ?.let { File(it.localPath).isCompleteCacheFileFor(attachment) } == true
+            }
+            .filterNot { attachment ->
+                container.attachmentFileService
+                    .createAttachmentCacheFile(attachment.id, attachment.fileName)
+                    .isCompleteCacheFileFor(attachment)
+            }
             .take(8)
             .forEach { attachment ->
                 viewModelScope.launch {
@@ -1760,6 +1815,20 @@ class ChatViewModel(
             message.hasProtectedContent && message.attachments.any { it.id == attachment.id }
         }
 
+    private fun File.isCompleteCacheFileFor(attachment: AttachmentDto): Boolean {
+        if (!isFile) {
+            return false
+        }
+
+        val actualSize = length()
+        if (actualSize <= 0L) {
+            return false
+        }
+
+        val expectedSize = attachment.fileSizeBytes
+        return expectedSize <= 0L || actualSize == expectedSize
+    }
+
     private fun toggleVoiceAttachmentPlayback(attachment: AttachmentDto) {
         viewModelScope.launch {
             runCatching {
@@ -1881,13 +1950,19 @@ class ChatViewModel(
     }
 
     private fun findMatchingPendingLocalMessageId(state: ChatUiState, serverMessage: MessageDto): String? {
-        if (serverMessage.isLocalMessage() || state.sendingLocalMessageIds.isEmpty()) {
+        if (serverMessage.isLocalMessage()) {
             return null
         }
 
+        serverMessage.clientMessageId?.let { clientMessageId ->
+            state.messages.firstOrNull { localMessage ->
+                localMessage.isLocalMessage() && localMessage.clientMessageId == clientMessageId
+            }?.let { return it.id }
+        }
+
         return state.messages.firstOrNull { localMessage ->
-            state.sendingLocalMessageIds.contains(localMessage.id) &&
+            localMessage.isLocalMessage() &&
-                localMessage.sender.id == serverMessage.sender.id &&
+            localMessage.sender.id == serverMessage.sender.id &&
                 localMessage.text == serverMessage.text &&
                 localMessage.attachments.isEmpty() &&
                 serverMessage.attachments.isEmpty() &&
@@ -2097,7 +2172,7 @@ internal fun MessageDto.canManage(currentUserId: String?, canPostAsChannel: Bool
 internal fun MessageDto.canDelete(currentUserId: String?): Boolean =
     currentUserId != null && deletedAt == null
 
-private fun MessageDto.isLocalMessage(): Boolean = id.startsWith(LocalMessageIdPrefix)
+private fun MessageDto.isLocalMessage(): Boolean = id.startsWith(ClientMessageIds.LocalPrefix)
 
 private fun searchLoadedMessageIds(query: String, messages: List<MessageDto>): List<String> {
     val normalizedQuery = query.trim()

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/chats/ChatsScreen.kt

@@ -73,6 +73,7 @@ import com.seven.ikar.kotlin.core.model.ChatSummaryDto
 import com.seven.ikar.kotlin.core.model.ChatType
 import com.seven.ikar.kotlin.core.model.StoryDto
 import com.seven.ikar.kotlin.core.network.ServerConfig
+import com.seven.ikar.kotlin.core.realtime.RealtimeConnectionStage
 import com.seven.ikar.kotlin.core.settings.ChatListLayoutOption
 import com.seven.ikar.kotlin.core.settings.ChatSettingsSnapshot
 import com.seven.ikar.kotlin.core.settings.ChatSwipeLeftActionOption
@@ -125,7 +126,7 @@ fun ChatsScreen(
     onFilterChanged: (ChatListFilter) -> Unit,
     onQueryChanged: (String) -> Unit
 ) {
-    val isRealtimeConnected = !state.isLoading || state.chats.isNotEmpty()
+    val isRealtimeConnected = state.realtimeStage == RealtimeConnectionStage.Connected
     val previewMaxLines = if (chatSettings.chatListLayout == ChatListLayoutOption.ThreeLine) 2 else 1
     val chatListState = rememberLazyListState()
     var isStoriesHeaderVisible by remember { mutableStateOf(false) }
@@ -188,8 +189,8 @@ fun ChatsScreen(
                 .nestedScroll(storyHeaderNestedScrollConnection)
         ) {
             Column(
-                modifier = Modifier.padding(start = 18.dp, top = 16.dp, end = 18.dp, bottom = 12.dp),
+                modifier = Modifier.padding(start = 14.dp, top = 8.dp, end = 14.dp, bottom = 6.dp),
-                verticalArrangement = Arrangement.spacedBy(12.dp)
+                verticalArrangement = Arrangement.spacedBy(8.dp)
             ) {
                 when {
                     state.isSelectionMode && state.isShareMode -> {
@@ -247,8 +248,11 @@ fun ChatsScreen(
                     )
                 }
 
-                TextButton(onClick = onGlobalSearchClick) {
+                TextButton(
-                    Text("Глобальный поиск: сообщения, медиа, файлы и ссылки")
+                    onClick = onGlobalSearchClick,
+                    contentPadding = androidx.compose.foundation.layout.PaddingValues(horizontal = 4.dp, vertical = 0.dp)
+                ) {
+                    Text("Поиск по сообщениям и файлам", style = MaterialTheme.typography.labelMedium)
                 }
 
                 state.pendingShare?.let { pendingShare ->
@@ -327,7 +331,7 @@ fun ChatsScreen(
                             }
                         }
                     }
-                    item { Box(modifier = Modifier.padding(bottom = 132.dp)) }
+                    item { Box(modifier = Modifier.padding(bottom = 104.dp)) }
                 }
 
                 if (!state.isSelectionMode && !state.isShareMode) {
@@ -336,7 +340,7 @@ fun ChatsScreen(
                         contentDescription = "Новое сообщение",
                         modifier = Modifier
                             .align(Alignment.BottomEnd)
-                            .padding(end = 20.dp, bottom = 126.dp),
+                            .padding(end = 16.dp, bottom = 98.dp),
                         onClick = onDiscoverClick
                     )
                 }
@@ -347,7 +351,7 @@ fun ChatsScreen(
             selectedTab = IkarMainMenuTab.Chats,
             modifier = Modifier
                 .align(Alignment.BottomCenter)
-                .padding(horizontal = 8.dp, vertical = 18.dp),
+                .padding(horizontal = 8.dp, vertical = 8.dp),
             onChatsClick = {},
             onContactsClick = onContactsClick,
             onSettingsClick = onSettingsClick,
@@ -412,7 +416,7 @@ private fun ChatsBrandHeader(
     onStoriesClick: () -> Unit
 ) {
     Row(
-        horizontalArrangement = Arrangement.spacedBy(12.dp),
+        horizontalArrangement = Arrangement.spacedBy(8.dp),
         verticalAlignment = Alignment.CenterVertically
     ) {
         StoriesClusterButton(
@@ -424,12 +428,16 @@ private fun ChatsBrandHeader(
         Column(verticalArrangement = Arrangement.spacedBy(0.dp)) {
             Text(
                 text = if (isRealtimeConnected) "ИКАР" else "Соединение...",
-                style = MaterialTheme.typography.displayMedium.copy(
+                style = MaterialTheme.typography.titleLarge.copy(
-                    letterSpacing = if (isRealtimeConnected) 3.sp else 0.sp
+                    letterSpacing = if (isRealtimeConnected) 2.sp else 0.sp
                 ),
                 color = TelegramBlue
             )
-            Text("Чаты", style = MaterialTheme.typography.bodySmall, color = TelegramInkMuted)
+            Text(
+                if (isRealtimeConnected) "Чаты" else "Повторное подключение",
+                style = MaterialTheme.typography.labelSmall,
+                color = TelegramInkMuted
+            )
         }
     }
 }
@@ -939,7 +947,11 @@ private fun SwipeableChatListRow(
                 verticalAlignment = Alignment.CenterVertically
             ) {
                 Row(horizontalArrangement = Arrangement.spacedBy(8.dp), verticalAlignment = Alignment.CenterVertically) {
-                    Icon(Icons.Outlined.PushPin, contentDescription = null, tint = TelegramBlue)
+                    Icon(
+                        Icons.Outlined.PushPin,
+                        contentDescription = if (chatItem.chat.isPinned) "Открепить чат" else "Закрепить чат",
+                        tint = TelegramBlue
+                    )
                     Text(
                         if (chatItem.chat.isPinned) "Открепить" else "Закрепить",
                         style = MaterialTheme.typography.labelLarge,
@@ -958,7 +970,11 @@ private fun SwipeableChatListRow(
                         style = MaterialTheme.typography.labelLarge,
                         color = TelegramBlue
                     )
-                    Icon(leftSwipeIcon, contentDescription = null, tint = TelegramBlue)
+                    Icon(
+                        leftSwipeIcon,
+                        contentDescription = chatItem.chat.leftSwipeActionLabel(swipeLeftAction),
+                        tint = TelegramBlue
+                    )
                 }
             }
         }
@@ -1009,18 +1025,18 @@ private fun ChatListRow(
         Row(
             modifier = Modifier
                 .fillMaxWidth()
-                .padding(horizontal = 8.dp, vertical = 2.dp)
+                .padding(horizontal = 6.dp, vertical = 1.dp)
                 .clip(MaterialTheme.shapes.large)
                 .background(rowBackground)
                 .combinedClickable(onClick = onClick, onLongClick = onLongClick)
-                .padding(horizontal = 8.dp, vertical = 10.dp),
+                .padding(horizontal = 8.dp, vertical = 7.dp),
-            horizontalArrangement = Arrangement.spacedBy(14.dp),
+            horizontalArrangement = Arrangement.spacedBy(10.dp),
             verticalAlignment = Alignment.CenterVertically
         ) {
             AvatarView(
                 imageUrl = avatarUrl,
                 title = chatItem.resolvedTitle,
-                size = 56.dp
+                size = 48.dp
             )
 
             Column(
@@ -1035,7 +1051,7 @@ private fun ChatListRow(
                     Text(
                         text = chatItem.resolvedTitle,
                         modifier = Modifier.weight(1f),
-                        style = MaterialTheme.typography.titleLarge,
+                        style = MaterialTheme.typography.titleMedium,
                         maxLines = 1,
                         overflow = TextOverflow.Ellipsis
                     )
@@ -1088,7 +1104,7 @@ private fun ChatListRow(
                 )
             }
         }
-        IkarRowDivider(startIndent = 86.dp)
+        IkarRowDivider(startIndent = 72.dp)
     }
 }
 

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/chats/ChatsViewModel.kt

@@ -13,6 +13,7 @@ import com.seven.ikar.kotlin.core.model.ChatStateRequest
 import com.seven.ikar.kotlin.core.model.ChatSummaryDto
 import com.seven.ikar.kotlin.core.model.ChatType
 import com.seven.ikar.kotlin.core.model.StoryDto
+import com.seven.ikar.kotlin.core.realtime.RealtimeConnectionStage
 import com.seven.ikar.kotlin.feature.share.PendingExternalShare
 import com.seven.ikar.kotlin.ui.formatLastActivity
 import kotlinx.coroutines.Dispatchers
@@ -69,7 +70,8 @@ data class ChatsUiState(
     val showDeleteForEveryoneOption: Boolean = false,
     val deleteForEveryoneLabel: String = DefaultDeleteForEveryoneLabel,
     val isDeletingSelected: Boolean = false,
-    val selectionStartedFromSwipeDelete: Boolean = false
+    val selectionStartedFromSwipeDelete: Boolean = false,
+    val realtimeStage: RealtimeConnectionStage = RealtimeConnectionStage.Disconnected
 ) {
     val isShareMode: Boolean
         get() = pendingShare != null
@@ -582,6 +584,14 @@ class ChatsViewModel(private val container: AppContainer) : ViewModel() {
     }
 
     private fun attachRealtime() {
+        viewModelScope.launch {
+            container.realtimeService.stage.collect { stage ->
+                _uiState.value = _uiState.value.copy(realtimeStage = stage)
+            }
+        }
+        viewModelScope.launch {
+            container.realtimeService.connectionRestored.collect { scheduleRefresh() }
+        }
         viewModelScope.launch {
             container.realtimeService.chatCreated.collect { scheduleRefresh() }
         }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/login/LoginScreen.kt

@@ -29,6 +29,8 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.input.KeyboardType
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.res.stringResource
+import com.seven.ikar.kotlin.R
 
 @Composable
 fun LoginScreen(
@@ -88,13 +90,17 @@ fun LoginScreen(
                     verticalArrangement = Arrangement.spacedBy(4.dp)
                 ) {
                     Text(
-                        text = state.pageTitle,
+                        text = stringResource(
+                            if (state.isAwaitingCode) R.string.login_verify_email_title else R.string.login_title
+                        ),
                         style = MaterialTheme.typography.headlineSmall,
                         color = Color.White,
                         fontWeight = FontWeight.SemiBold
                     )
                     Text(
-                        text = state.subtitle,
+                        text = stringResource(
+                            if (state.isAwaitingCode) R.string.login_code_subtitle else R.string.login_subtitle
+                        ),
                         style = MaterialTheme.typography.bodyMedium,
                         color = Color(0xFFDDEEFF)
                     )
@@ -111,7 +117,7 @@ fun LoginScreen(
                     verticalArrangement = Arrangement.spacedBy(16.dp)
                 ) {
                     Text(
-                        text = "АККАУНТ",
+                        text = stringResource(R.string.login_account_section),
                         style = MaterialTheme.typography.labelLarge,
                         color = Color(0xFF5A8EB2),
                         fontWeight = FontWeight.SemiBold
@@ -122,7 +128,7 @@ fun LoginScreen(
                             value = state.email,
                             onValueChange = onEmailChanged,
                             modifier = Modifier.fillMaxWidth(),
-                            label = { Text("Электронная почта") },
+                            label = { Text(stringResource(R.string.login_email)) },
                             keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Email),
                             singleLine = true
                         )
@@ -131,7 +137,7 @@ fun LoginScreen(
                             value = state.phoneNumber,
                             onValueChange = onPhoneNumberChanged,
                             modifier = Modifier.fillMaxWidth(),
-                            label = { Text("Номер телефона") },
+                            label = { Text(stringResource(R.string.login_phone)) },
                             keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Phone),
                             singleLine = true
                         )
@@ -147,7 +153,7 @@ fun LoginScreen(
                                     modifier = Modifier.padding(horizontal = 8.dp)
                                 )
                             } else {
-                                Text("Получить код")
+                                Text(stringResource(R.string.login_request_code))
                             }
                         }
                     }
@@ -164,12 +170,12 @@ fun LoginScreen(
                                 verticalArrangement = Arrangement.spacedBy(10.dp)
                             ) {
                                 Text(
-                                    text = "Подтверждение email",
+                                    text = stringResource(R.string.login_verify_email_title),
                                     style = MaterialTheme.typography.titleMedium,
                                     fontWeight = FontWeight.SemiBold
                                 )
                                 Text(
-                                    text = "Код отправлен на указанную электронную почту. Номер телефона будет привязан к аккаунту.",
+                                    text = stringResource(R.string.login_code_explanation),
                                     style = MaterialTheme.typography.bodyMedium,
                                     color = Color(0xFF617A8F)
                                 )
@@ -178,7 +184,7 @@ fun LoginScreen(
                                     value = state.verificationCode,
                                     onValueChange = onVerificationCodeChanged,
                                     modifier = Modifier.fillMaxWidth(),
-                                    label = { Text("Код подтверждения") },
+                                    label = { Text(stringResource(R.string.login_code)) },
                                     keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
                                     singleLine = true
                                 )
@@ -188,7 +194,7 @@ fun LoginScreen(
                                         value = state.displayName,
                                         onValueChange = onDisplayNameChanged,
                                         modifier = Modifier.fillMaxWidth(),
-                                        label = { Text("Ваше имя") },
+                                        label = { Text(stringResource(R.string.login_display_name)) },
                                         singleLine = true
                                     )
                                 }
@@ -196,8 +202,7 @@ fun LoginScreen(
                                 Button(
                                     onClick = onVerifyCodeClick,
                                     enabled = !state.isLoading &&
-                                        state.verificationCode.isNotBlank() &&
+                                        state.verificationCode.isNotBlank(),
-                                        (!state.isNewAccount || state.displayName.isNotBlank()),
                                     contentPadding = PaddingValues(horizontal = 20.dp, vertical = 14.dp)
                                 ) {
                                     if (state.isLoading) {
@@ -206,7 +211,7 @@ fun LoginScreen(
                                             modifier = Modifier.padding(horizontal = 8.dp)
                                         )
                                     } else {
-                                        Text("Продолжить")
+                                    Text(stringResource(R.string.login_continue))
                                     }
                                 }
 
@@ -219,7 +224,7 @@ fun LoginScreen(
                                     ),
                                     contentPadding = PaddingValues(horizontal = 0.dp, vertical = 12.dp)
                                 ) {
-                                    Text("Изменить email или телефон")
+                                Text(stringResource(R.string.login_change_identity))
                                 }
                             }
                         }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/login/LoginViewModel.kt

@@ -38,7 +38,7 @@ data class LoginUiState(
         get() = isAwaitingCode
 
     val showDisplayName: Boolean
-        get() = isAwaitingCode && isNewAccount
+        get() = isAwaitingCode
 }
 
 class LoginViewModel(private val container: AppContainer) : ViewModel() {
@@ -103,8 +103,7 @@ class LoginViewModel(private val container: AppContainer) : ViewModel() {
             state.challengeId.isBlank() ||
             state.email.isBlank() ||
             state.phoneNumber.isBlank() ||
-            state.verificationCode.isBlank() ||
+            state.verificationCode.isBlank()
-            (state.isNewAccount && state.displayName.isBlank())
         ) {
             return
         }

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/transfer/TextMessageWorker.kt

@@ -0,0 +1,62 @@
+package com.seven.ikar.kotlin.feature.transfer
+
+import android.content.Context
+import androidx.work.CoroutineWorker
+import androidx.work.WorkerParameters
+import com.seven.ikar.kotlin.app.IkarNativeApp
+import com.seven.ikar.kotlin.core.local.TransferQueueStatus
+import com.seven.ikar.kotlin.core.local.TransferQueueTypes
+
+class TextMessageWorker(
+    appContext: Context,
+    params: WorkerParameters
+) : CoroutineWorker(appContext, params) {
+    override suspend fun doWork(): Result {
+        val groupId = inputData.getString(KeyGroupId) ?: return Result.failure()
+        val container = (applicationContext as IkarNativeApp).container
+        val dao = container.localDatabase.transferQueueDao()
+        val item = dao.getGroup(groupId).firstOrNull() ?: return Result.success()
+        if (item.type != TransferQueueTypes.TextMessage) {
+            return Result.failure()
+        }
+
+        val chatId = item.chatId ?: return Result.failure()
+        val text = item.text?.takeIf(String::isNotBlank) ?: return Result.failure()
+        val clientMessageId = item.clientMessageId ?: groupId
+        dao.updateGroupStatus(groupId, TransferQueueStatus.Running, 25, null, System.currentTimeMillis())
+
+        return runCatching {
+            container.executeAuthorized { session ->
+                val message = container.apiClient.sendMessage(
+                    chatId = chatId,
+                    text = text,
+                    accessToken = session.accessToken,
+                    replyToMessageId = item.replyToMessageId,
+                    clientMessageId = clientMessageId
+                )
+                container.chatMessageCache.upsertMessages(session.user.id, chatId, listOf(message))
+            }
+        }.fold(
+            onSuccess = {
+                dao.updateGroupStatus(groupId, TransferQueueStatus.Completed, 100, null, System.currentTimeMillis())
+                container.realtimeService.notifyChatsChangedLocally()
+                Result.success()
+            },
+            onFailure = { error ->
+                dao.updateGroupStatus(
+                    groupId,
+                    TransferQueueStatus.Failed,
+                    0,
+                    error.message,
+                    System.currentTimeMillis()
+                )
+                if (runAttemptCount < MaxAutomaticRetries) Result.retry() else Result.failure()
+            }
+        )
+    }
+
+    companion object {
+        const val KeyGroupId = "group_id"
+        private const val MaxAutomaticRetries = 5
+    }
+}

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/feature/transfer/TransferQueueRepository.kt

@@ -15,6 +15,7 @@ import com.seven.ikar.kotlin.core.model.AttachmentDto
 import com.seven.ikar.kotlin.core.model.StoryVisibility
 import com.seven.ikar.kotlin.feature.chat.LocalAttachmentFile
 import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.first
 import java.util.UUID
 
 class TransferQueueRepository(
@@ -27,6 +28,46 @@ class TransferQueueRepository(
     fun observeActiveStoryUploads(): Flow<List<TransferQueueEntity>> =
         dao.observeActiveStoryUploads()
 
+    suspend fun enqueueTextMessage(
+        chatId: String,
+        text: String,
+        replyToMessageId: String?,
+        clientMessageId: String
+    ): String {
+        require(text.isNotBlank()) { "Message text is required." }
+
+        val now = System.currentTimeMillis()
+        dao.upsert(
+            listOf(
+                TransferQueueEntity(
+                    id = UUID.randomUUID().toString(),
+                    groupId = clientMessageId,
+                    type = TransferQueueTypes.TextMessage,
+                    status = TransferQueueStatus.Queued,
+                    chatId = chatId,
+                    text = text,
+                    replyToMessageId = replyToMessageId,
+                    clientMessageId = clientMessageId,
+                    attachmentId = null,
+                    storyVisibility = null,
+                    hasProtectedContent = false,
+                    ttlSeconds = null,
+                    fileName = "",
+                    contentType = "text/plain",
+                    fileSizeBytes = 0,
+                    localPath = "",
+                    sortOrder = 0,
+                    progressPercent = 0,
+                    errorMessage = null,
+                    createdAtMillis = now,
+                    updatedAtMillis = now
+                )
+            )
+        )
+        scheduler.enqueueTextMessage(clientMessageId)
+        return clientMessageId
+    }
+
     suspend fun enqueueUpload(
         chatId: String,
         text: String?,
@@ -47,6 +88,7 @@ class TransferQueueRepository(
                     chatId = chatId,
                     text = text?.takeIf { it.isNotBlank() },
                     replyToMessageId = replyToMessageId,
+                    clientMessageId = null,
                     attachmentId = null,
                     storyVisibility = null,
                     hasProtectedContent = false,
@@ -88,6 +130,7 @@ class TransferQueueRepository(
                     chatId = null,
                     text = text?.takeIf { it.isNotBlank() },
                     replyToMessageId = null,
+                    clientMessageId = null,
                     attachmentId = null,
                     storyVisibility = visibility.name,
                     hasProtectedContent = hasProtectedContent,
@@ -109,6 +152,7 @@ class TransferQueueRepository(
     }
 
     suspend fun enqueueDownload(chatId: String, attachment: AttachmentDto): String {
+        dao.findActiveDownloadGroup(attachment.id)?.let { return it }
         val groupId = UUID.randomUUID().toString()
         val now = System.currentTimeMillis()
         dao.upsert(
@@ -121,6 +165,7 @@ class TransferQueueRepository(
                     chatId = chatId,
                     text = null,
                     replyToMessageId = null,
+                    clientMessageId = null,
                     attachmentId = attachment.id,
                     storyVisibility = null,
                     hasProtectedContent = false,
@@ -141,10 +186,22 @@ class TransferQueueRepository(
         return groupId
     }
 
+    suspend fun awaitCompletion(groupId: String): List<TransferQueueEntity> =
+        dao.observeGroup(groupId).first { items ->
+            items.isNotEmpty() && items.all { item ->
+                item.status == TransferQueueStatus.Completed || item.status == TransferQueueStatus.Failed
+            }
+        }.also { items ->
+            items.firstOrNull { it.status == TransferQueueStatus.Failed }?.let { failed ->
+                throw IllegalStateException(failed.errorMessage ?: "Transfer failed.")
+            }
+        }
+
     suspend fun retry(groupId: String) {
         val type = dao.getGroup(groupId).firstOrNull()?.type
         dao.updateGroupStatus(groupId, TransferQueueStatus.Queued, 0, null, System.currentTimeMillis())
         when (type) {
+            TransferQueueTypes.TextMessage -> scheduler.enqueueTextMessage(groupId)
             TransferQueueTypes.Download -> scheduler.enqueueDownload(groupId)
             TransferQueueTypes.StoryUpload -> scheduler.enqueueStoryUpload(groupId)
             else -> scheduler.enqueueUpload(groupId)
@@ -172,6 +229,15 @@ class TransferWorkScheduler(context: Context) {
         workManager.enqueueUniqueWork(uploadWorkName(groupId), ExistingWorkPolicy.REPLACE, request)
     }
 
+    fun enqueueTextMessage(groupId: String) {
+        val request = OneTimeWorkRequestBuilder<TextMessageWorker>()
+            .setInputData(workDataOf(TextMessageWorker.KeyGroupId to groupId))
+            .setConstraints(networkConstraints)
+            .build()
+
+        workManager.enqueueUniqueWork(textMessageWorkName(groupId), ExistingWorkPolicy.KEEP, request)
+    }
+
     fun enqueueStoryUpload(groupId: String) {
         val request = OneTimeWorkRequestBuilder<AttachmentUploadWorker>()
             .setInputData(workDataOf(AttachmentUploadWorker.KeyGroupId to groupId))
@@ -191,6 +257,7 @@ class TransferWorkScheduler(context: Context) {
     }
 
     fun cancel(groupId: String) {
+        workManager.cancelUniqueWork(textMessageWorkName(groupId))
         workManager.cancelUniqueWork(uploadWorkName(groupId))
         workManager.cancelUniqueWork(storyUploadWorkName(groupId))
         workManager.cancelUniqueWork(downloadWorkName(groupId))
@@ -198,6 +265,8 @@ class TransferWorkScheduler(context: Context) {
 
     private fun uploadWorkName(groupId: String): String = "upload-$groupId"
 
+    private fun textMessageWorkName(groupId: String): String = "text-message-$groupId"
+
     private fun storyUploadWorkName(groupId: String): String = "story-upload-$groupId"
 
     private fun downloadWorkName(groupId: String): String = "download-$groupId"

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/ui/AuthenticatedAsyncImage.kt

@@ -6,6 +6,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.platform.LocalContext
 import coil.compose.AsyncImage
+import coil.compose.AsyncImagePainter
 import coil.request.CachePolicy
 import coil.request.ImageRequest
 import java.security.MessageDigest
@@ -16,7 +17,8 @@ fun AuthenticatedAsyncImage(
     accessToken: String? = null,
     contentDescription: String,
     modifier: Modifier = Modifier,
-    contentScale: ContentScale = ContentScale.Crop
+    contentScale: ContentScale = ContentScale.Crop,
+    onSuccess: ((AsyncImagePainter.State.Success) -> Unit)? = null
 ) {
     if (imageUrl.isNullOrBlank()) {
         return
@@ -45,7 +47,8 @@ fun AuthenticatedAsyncImage(
         model = request,
         contentDescription = contentDescription,
         modifier = modifier,
-        contentScale = contentScale
+        contentScale = contentScale,
+        onSuccess = onSuccess
     )
 }
 

src/Ikar.AndroidKotlin/app/src/main/java/com/seven/ikar/kotlin/ui/IkarChrome.kt

@@ -524,8 +524,8 @@ fun IkarFloatingMainMenu(
         Row(
             modifier = Modifier
                 .border(1.dp, TelegramFloatingBorder, RoundedCornerShape(32.dp))
-                .padding(horizontal = 12.dp, vertical = 10.dp),
+                .padding(horizontal = 8.dp, vertical = 6.dp),
-            horizontalArrangement = Arrangement.spacedBy(6.dp)
+            horizontalArrangement = Arrangement.spacedBy(4.dp)
         ) {
             val unreadChatsCount = LocalUnreadChatsCount.current
             IkarFloatingMenuItem(
@@ -573,9 +573,9 @@ private fun IkarFloatingMenuItem(
             .clip(shape)
             .clickable(onClick = onClick)
             .background(backgroundColor)
-            .padding(horizontal = 10.dp, vertical = 8.dp),
+            .padding(horizontal = 8.dp, vertical = 5.dp),
         horizontalAlignment = Alignment.CenterHorizontally,
-        verticalArrangement = Arrangement.spacedBy(4.dp)
+        verticalArrangement = Arrangement.spacedBy(2.dp)
     ) {
         Box(
             modifier = Modifier.size(28.dp),

src/Ikar.AndroidKotlin/app/src/main/res/values-en/strings.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">Ikar</string>
+    <string name="login_title">Sign in to IKAR</string>
+    <string name="login_verify_email_title">Verify your email</string>
+    <string name="login_subtitle">Enter your email and phone number. The code will only be sent by email.</string>
+    <string name="login_code_subtitle">Enter the code sent to your email address.</string>
+    <string name="login_account_section">ACCOUNT</string>
+    <string name="login_email">Email</string>
+    <string name="login_phone">Phone number</string>
+    <string name="login_request_code">Send code</string>
+    <string name="login_code">Verification code</string>
+    <string name="login_display_name">Your name (for a new account)</string>
+    <string name="login_continue">Continue</string>
+    <string name="login_change_identity">Change email or phone</string>
+    <string name="login_code_explanation">The code was sent by email. Your phone number will be linked to the account.</string>
+</resources>

src/Ikar.AndroidKotlin/app/src/main/res/values/strings.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">Икар</string>
+    <string name="login_title">Вход в ИКАР</string>
+    <string name="login_verify_email_title">Подтвердите email</string>
+    <string name="login_subtitle">Введите электронную почту и номер телефона. Код придёт только на email.</string>
+    <string name="login_code_subtitle">Введите код, отправленный на указанную электронную почту.</string>
+    <string name="login_account_section">АККАУНТ</string>
+    <string name="login_email">Электронная почта</string>
+    <string name="login_phone">Номер телефона</string>
+    <string name="login_request_code">Получить код</string>
+    <string name="login_code">Код подтверждения</string>
+    <string name="login_display_name">Ваше имя (для нового аккаунта)</string>
+    <string name="login_continue">Продолжить</string>
+    <string name="login_change_identity">Изменить email или телефон</string>
+    <string name="login_code_explanation">Код отправлен на указанную электронную почту. Номер телефона будет привязан к аккаунту.</string>
+</resources>

src/Ikar.AndroidKotlin/app/src/test/java/com/seven/ikar/kotlin/core/model/ClientMessageIdsTest.kt

@@ -0,0 +1,21 @@
+package com.seven.ikar.kotlin.core.model
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertNotEquals
+import org.junit.Test
+
+class ClientMessageIdsTest {
+    @Test
+    fun localIdRoundTripsClientId() {
+        val clientId = ClientMessageIds.newClientId()
+        assertEquals(clientId, ClientMessageIds.clientIdFromLocalId(ClientMessageIds.localId(clientId)))
+    }
+
+    @Test
+    fun generatedIdsAreUniqueAndNonLocalValuesAreRejected() {
+        assertNotEquals(ClientMessageIds.newClientId(), ClientMessageIds.newClientId())
+        assertNull(ClientMessageIds.clientIdFromLocalId("server-message-id"))
+        assertNull(ClientMessageIds.clientIdFromLocalId(ClientMessageIds.LocalPrefix))
+    }
+}

src/Ikar.Server.Tests/AuthEmailControllerTests.cs

@@ -152,7 +152,7 @@ public sealed class AuthEmailControllerTests
     }
 
     [Fact]
-    public async Task RequestPhoneCode_NewPhone_DoesNotRegister()
+    public async Task RequestPhoneCode_IsDisabled()
     {
         await using var database = new SqliteTestDatabase();
         await using var dbContext = await database.CreateContextAsync();
@@ -162,7 +162,8 @@ public sealed class AuthEmailControllerTests
             new RequestPhoneCodeRequest("+10000009999"),
             CancellationToken.None);
 
-        Assert.IsType<NotFoundObjectResult>(result.Result);
+        var response = Assert.IsType<ObjectResult>(result.Result);
+        Assert.Equal(StatusCodes.Status410Gone, response.StatusCode);
     }
 
     private static AuthController CreateController(
@@ -174,7 +175,6 @@ public sealed class AuthEmailControllerTests
             dbContext,
             new TokenService(dbContext, Options.Create(new JwtOptions())),
             new PresenceTracker(),
-            new PhoneAuthChallengeStore(),
             emailChallengeStore,
             emailCodeSender);
         controller.ControllerContext = new ControllerContext

src/Ikar.Server.Tests/ChannelMembersControllerTests.cs

@@ -519,7 +519,7 @@ public sealed class ChannelMembersControllerTests
                 new UploadAttachmentRequest
                 {
                     Text = "Photo post",
-                    File = CreateFormFile([1, 2, 3], "photo.jpg", "image/jpeg")
+                    File = CreateFormFile([0xFF, 0xD8, 0xFF, 0xE0], "photo.jpg", "image/jpeg")
                 },
                 CancellationToken.None);
 
@@ -570,8 +570,8 @@ public sealed class ChannelMembersControllerTests
                     Text = "Gallery",
                     Files =
                     [
-                        CreateFormFile([1, 2, 3], "first.jpg", "image/jpeg"),
+                        CreateFormFile([0xFF, 0xD8, 0xFF, 0xE0], "first.jpg", "image/jpeg"),
-                        CreateFormFile([4, 5, 6], "second.jpg", "image/jpeg")
+                        CreateFormFile([0xFF, 0xD8, 0xFF, 0xE1], "second.jpg", "image/jpeg")
                     ]
                 },
                 CancellationToken.None);

src/Ikar.Server.Tests/ReliabilityAndSecurityTests.cs

@@ -0,0 +1,166 @@
+using Ikar.Server.Data.Entities;
+using Ikar.Server.Infrastructure.Auth;
+using Ikar.Server.Infrastructure.Calls;
+using Ikar.Server.Infrastructure.Push;
+using Ikar.Server.Infrastructure.Storage;
+using Ikar.Shared;
+using Microsoft.AspNetCore.Http;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Ikar.Server.Tests;
+
+public sealed class ReliabilityAndSecurityTests
+{
+    [Fact]
+    public void EmailChallenge_EnforcesResendDelayAndAttemptLimit()
+    {
+        var store = new EmailAuthChallengeStore();
+        var challenge = store.Create("user@example.com", "10000000000", isRegistered: true);
+
+        var rateLimit = Assert.Throws<AuthChallengeRateLimitException>(() =>
+            store.Create("user@example.com", "10000000000", isRegistered: true));
+        Assert.True(rateLimit.RetryAfter > TimeSpan.Zero);
+
+        for (var attempt = 0; attempt < 5; attempt++)
+        {
+            Assert.Null(store.Consume(challenge.Id, challenge.NormalizedEmail, challenge.NormalizedPhoneNumber, "000000"));
+        }
+
+        Assert.Null(store.Consume(challenge.Id, challenge.NormalizedEmail, challenge.NormalizedPhoneNumber, challenge.Code));
+    }
+
+    [Fact]
+    public void AttachmentInspector_UsesFileSignatureInsteadOfClaimedMimeType()
+    {
+        using var fakeImageStream = new MemoryStream("not-an-image"u8.ToArray());
+        var fakeImage = new FormFile(fakeImageStream, 0, fakeImageStream.Length, "file", "photo.jpg")
+        {
+            Headers = new HeaderDictionary(),
+            ContentType = "image/jpeg"
+        };
+        Assert.Equal("application/octet-stream", AttachmentContentInspector.Inspect(fakeImage).ContentType);
+
+        using var jpegStream = new MemoryStream([0xFF, 0xD8, 0xFF, 0xE0]);
+        var jpeg = new FormFile(jpegStream, 0, jpegStream.Length, "file", "photo.bin")
+        {
+            Headers = new HeaderDictionary(),
+            ContentType = "application/octet-stream"
+        };
+        var inspectedJpeg = AttachmentContentInspector.Inspect(jpeg);
+        Assert.Equal("image/jpeg", inspectedJpeg.ContentType);
+        Assert.True(inspectedJpeg.IsImage);
+    }
+
+    [Fact]
+    public void CallStore_ExpiresUnansweredCalls()
+    {
+        var store = new CallSessionStore();
+        Assert.True(store.TryCreate(
+            Guid.NewGuid(),
+            Guid.NewGuid(),
+            Guid.NewGuid(),
+            CallMediaType.Audio,
+            out var created,
+            out _));
+
+        var expired = store.DrainExpired(
+            created!.CreatedAt.AddSeconds(61),
+            TimeSpan.FromSeconds(60),
+            TimeSpan.FromHours(8));
+
+        var ended = Assert.Single(expired);
+        Assert.Equal("no_answer", ended.EndReason);
+        Assert.Equal(CallSessionState.Ended, ended.State);
+    }
+
+    [Fact]
+    public async Task SendMessage_ReusingClientMessageId_ReturnsOriginalMessage()
+    {
+        await using var database = new SqliteTestDatabase();
+        await using var dbContext = await database.CreateContextAsync();
+        var user = new User
+        {
+            Username = "reliable_sender",
+            NormalizedUsername = "RELIABLE_SENDER",
+            DisplayName = "Reliable Sender",
+            PasswordHash = "test"
+        };
+        var chat = new Chat
+        {
+            Type = ChatType.Group,
+            Title = "Idempotency",
+            CreatedBy = user,
+            CreatedById = user.Id
+        };
+        chat.Members.Add(new ChatMember
+        {
+            Chat = chat,
+            ChatId = chat.Id,
+            User = user,
+            UserId = user.Id,
+            IsOwner = true,
+            Role = ChatMemberRole.Owner
+        });
+        dbContext.AddRange(user, chat);
+        await dbContext.SaveChangesAsync();
+
+        var controller = ControllerTestFixture.CreateChatsController(dbContext, user.Id);
+        var clientMessageId = Guid.NewGuid();
+        var request = new SendMessageRequest("Send once", ClientMessageId: clientMessageId);
+        var first = ControllerTestFixture.ValueOf(await controller.SendMessage(chat.Id, request, CancellationToken.None));
+        var second = ControllerTestFixture.ValueOf(await controller.SendMessage(chat.Id, request, CancellationToken.None));
+
+        Assert.Equal(first.Id, second.Id);
+        Assert.Equal(clientMessageId, second.ClientMessageId);
+        Assert.Equal(1, await dbContext.Messages.CountAsync());
+    }
+
+    [Fact]
+    public async Task PushOutbox_IsCommittedWithTheMessageAndDeduplicated()
+    {
+        await using var database = new SqliteTestDatabase();
+        await using var dbContext = await database.CreateContextAsync();
+        var user = new User
+        {
+            Username = "outbox_sender",
+            NormalizedUsername = "OUTBOX_SENDER",
+            DisplayName = "Outbox Sender",
+            PasswordHash = "test"
+        };
+        var chat = new Chat
+        {
+            Type = ChatType.Group,
+            Title = "Outbox",
+            CreatedBy = user,
+            CreatedById = user.Id
+        };
+        chat.Members.Add(new ChatMember
+        {
+            Chat = chat,
+            ChatId = chat.Id,
+            User = user,
+            UserId = user.Id,
+            IsOwner = true,
+            Role = ChatMemberRole.Owner
+        });
+        var message = new Message
+        {
+            Chat = chat,
+            ChatId = chat.Id,
+            Sender = user,
+            SenderId = user.Id,
+            Text = "Persist with outbox"
+        };
+        dbContext.Messages.Add(message);
+
+        using var services = new ServiceCollection().BuildServiceProvider();
+        var queue = new PushDispatchQueue(services.GetRequiredService<IServiceScopeFactory>());
+        queue.StageMessages(dbContext, message, message);
+        await dbContext.SaveChangesAsync();
+
+        var outbox = Assert.Single(await dbContext.PushDispatchOutbox.AsNoTracking().ToListAsync());
+        Assert.Equal(message.Id, outbox.MessageId);
+        Assert.Equal($"message:{message.Id:D}", outbox.DeduplicationKey);
+    }
+}

src/Ikar.Server/Controllers/AuthController.cs

@@ -16,7 +16,6 @@ public sealed class AuthController(
     IkarDbContext dbContext,
     TokenService tokenService,
     PresenceTracker presenceTracker,
-    PhoneAuthChallengeStore phoneAuthChallengeStore,
     EmailAuthChallengeStore emailAuthChallengeStore,
     IEmailCodeSender emailCodeSender) : ControllerBase
 {
@@ -135,77 +134,26 @@ public sealed class AuthController(
 
     [HttpPost("request-code")]
     [AllowAnonymous]
-    public async Task<ActionResult<PhoneCodeChallengeDto>> RequestPhoneCode(
+    public Task<ActionResult<PhoneCodeChallengeDto>> RequestPhoneCode(
         RequestPhoneCodeRequest request,
         CancellationToken cancellationToken)
     {
-        var normalizedPhoneNumber = PhoneNumberNormalizer.Normalize(request.PhoneNumber);
+        return Task.FromResult<ActionResult<PhoneCodeChallengeDto>>(
-        if (normalizedPhoneNumber is null)
+            StatusCode(
-        {
+                StatusCodes.Status410Gone,
-            return ValidationProblem("Valid phone number is required.");
+                new { error = "Phone-code authentication is disabled. Request a code by email." }));
-        }
-
-        var user = await dbContext.Users
-            .AsNoTracking()
-            .SingleOrDefaultAsync(x => x.NormalizedPhoneNumber == normalizedPhoneNumber, cancellationToken);
-        if (user is null)
-        {
-            return NotFound("Phone code login is available only for existing accounts. Register by email.");
-        }
-
-        if (user?.IsBlocked == true)
-        {
-            return StatusCode(StatusCodes.Status423Locked, "User is blocked.");
-        }
-
-        var challenge = phoneAuthChallengeStore.Create(normalizedPhoneNumber, isRegistered: true);
-        return Ok(new PhoneCodeChallengeDto(
-            challenge.Id,
-            challenge.ExpiresAt,
-            challenge.Code,
-            challenge.IsRegistered));
     }
 
     [HttpPost("verify-code")]
     [AllowAnonymous]
-    public async Task<ActionResult<AuthSessionDto>> VerifyPhoneCode(
+    public Task<ActionResult<AuthSessionDto>> VerifyPhoneCode(
         VerifyPhoneCodeRequest request,
         CancellationToken cancellationToken)
     {
-        var normalizedPhoneNumber = PhoneNumberNormalizer.Normalize(request.PhoneNumber);
+        return Task.FromResult<ActionResult<AuthSessionDto>>(
-        if (normalizedPhoneNumber is null)
+            StatusCode(
-        {
+                StatusCodes.Status410Gone,
-            return ValidationProblem("Valid phone number is required.");
+                new { error = "Phone-code authentication is disabled. Verify a code sent by email." }));
-        }
-
-        var challenge = phoneAuthChallengeStore.Consume(
-            request.ChallengeId?.Trim() ?? string.Empty,
-            normalizedPhoneNumber,
-            request.Code?.Trim() ?? string.Empty);
-        if (challenge is null)
-        {
-            return Unauthorized("Invalid or expired verification code.");
-        }
-
-        var user = await dbContext.Users.SingleOrDefaultAsync(
-            x => x.NormalizedPhoneNumber == normalizedPhoneNumber,
-            cancellationToken);
-
-        if (user is null)
-        {
-            return NotFound("Phone code login is available only for existing accounts. Register by email.");
-        }
-
-        if (user.IsBlocked)
-        {
-            return StatusCode(StatusCodes.Status423Locked, "User is blocked.");
-        }
-
-        var session = await tokenService.CreateSessionAsync(
-            user,
-            ClientVersionRequestReader.Read(Request),
-            cancellationToken);
-        return Ok(session with { User = user.ToDto(presenceTracker) });
     }
 
     [HttpPost("request-email-code")]
@@ -247,7 +195,18 @@ public sealed class AuthController(
             return StatusCode(StatusCodes.Status423Locked, "User is blocked.");
         }
 
-        var challenge = emailAuthChallengeStore.Create(normalizedEmail, normalizedPhoneNumber, user is not null);
+        EmailAuthChallengeStore.EmailAuthChallenge challenge;
+        try
+        {
+            challenge = emailAuthChallengeStore.Create(normalizedEmail, normalizedPhoneNumber, user is not null);
+        }
+        catch (AuthChallengeRateLimitException ex)
+        {
+            Response.Headers.RetryAfter = Math.Max(1, (int)Math.Ceiling(ex.RetryAfter.TotalSeconds)).ToString();
+            return StatusCode(
+                StatusCodes.Status429TooManyRequests,
+                new { error = "Please wait before requesting another email code." });
+        }
         try
         {
             await emailCodeSender.SendLoginCodeAsync(email, challenge.Code, challenge.ExpiresAt, cancellationToken);
@@ -261,7 +220,7 @@ public sealed class AuthController(
         return Ok(new EmailCodeChallengeDto(
             challenge.Id,
             challenge.ExpiresAt,
-            challenge.IsRegistered));
+            IsRegistered: false));
     }
 
     [HttpPost("verify-email-code")]

src/Ikar.Server/Controllers/BotApiController.cs

@@ -225,6 +225,7 @@ public sealed class BotApiController(
             message.DiscussionMessageId = discussionRootMessage.Id;
         }
 
+        pushDispatchQueue.StageMessages(dbContext, message, discussionRootMessage);
         await dbContext.SaveChangesAsync(cancellationToken);
 
         await NotifyMessageCreatedAsync(chat, message, cancellationToken);
@@ -377,6 +378,7 @@ public sealed class BotApiController(
                 message.DiscussionMessageId = discussionRootMessage.Id;
             }
 
+            pushDispatchQueue.StageMessages(dbContext, message, discussionRootMessage);
             await dbContext.SaveChangesAsync(cancellationToken);
         }
         catch
@@ -516,6 +518,7 @@ public sealed class BotApiController(
                 message.DiscussionMessageId = discussionRootMessage.Id;
             }
 
+            pushDispatchQueue.StageMessages(dbContext, message, discussionRootMessage);
             await dbContext.SaveChangesAsync(cancellationToken);
         }
         catch

src/Ikar.Server/Controllers/ChatsController.cs

@@ -1842,6 +1842,38 @@ public sealed class ChatsController(
             return StatusCode(StatusCodes.Status403Forbidden, "Only channel owners can publish.");
         }
 
+        if (request.ClientMessageId is not null)
+        {
+            var existingMessage = await dbContext.Messages
+                .AsNoTracking()
+                .SingleOrDefaultAsync(
+                    message => message.SenderId == userId && message.ClientMessageId == request.ClientMessageId,
+                    cancellationToken);
+            if (existingMessage is not null)
+            {
+                if (existingMessage.ChatId != chatId)
+                {
+                    return Conflict("Client message id is already used in another chat.");
+                }
+
+                var loadedExistingMessage = await LoadMessageForMemberAsync(
+                    chatId,
+                    existingMessage.Id,
+                    userId,
+                    cancellationToken);
+                if (loadedExistingMessage is null)
+                {
+                    return NotFound();
+                }
+
+                // Re-enqueueing is safe because the durable outbox deduplicates by message id.
+                // This repairs the narrow case where the original HTTP request committed the
+                // message but was interrupted before the push job could be persisted.
+                await pushDispatchQueue.EnqueueAsync(chatId, existingMessage.Id, cancellationToken);
+                return Ok(loadedExistingMessage.ToDto(presenceTracker, userId));
+            }
+        }
+
         var storyReply = request.StoryReplyStoryId is null
             ? null
             : await LoadVisibleStoryForReplyAsync(request.StoryReplyStoryId.Value, userId, cancellationToken);
@@ -1897,6 +1929,7 @@ public sealed class ChatsController(
             Chat = chat,
             SenderId = userId,
             Sender = sender,
+            ClientMessageId = request.ClientMessageId,
             PostedAsChannel = ShouldPostAsChannel(chat),
             AuthorSignature = ResolveChannelAuthorSignature(chat, sender),
             Text = text,
@@ -1928,6 +1961,7 @@ public sealed class ChatsController(
             message.DiscussionMessageId = discussionRootMessage.Id;
         }
 
+        pushDispatchQueue.StageMessages(dbContext, message, discussionRootMessage);
         await dbContext.SaveChangesAsync(cancellationToken);
 
         var loadedMessage = await LoadMessageForMemberAsync(chatId, message.Id, userId, cancellationToken)
@@ -2052,6 +2086,7 @@ public sealed class ChatsController(
                 forwardedMessage.DiscussionMessageId = discussionRootMessage.Id;
             }
 
+            pushDispatchQueue.StageMessages(dbContext, forwardedMessage, discussionRootMessage);
             await dbContext.SaveChangesAsync(cancellationToken);
         }
         catch
@@ -2176,6 +2211,10 @@ public sealed class ChatsController(
             shouldNotifyReaction = message.SenderId != userId;
         }
 
+        if (shouldNotifyReaction)
+        {
+            pushDispatchQueue.StageReaction(dbContext, chatId, messageId, userId, emoji);
+        }
         await dbContext.SaveChangesAsync(cancellationToken);
 
         var updatedMessage = await LoadMessageForMemberAsync(chatId, messageId, userId, cancellationToken)
@@ -2314,6 +2353,7 @@ public sealed class ChatsController(
                 message.DiscussionMessageId = discussionRootMessage.Id;
             }
 
+            pushDispatchQueue.StageMessages(dbContext, message, discussionRootMessage);
             await dbContext.SaveChangesAsync(cancellationToken);
         }
         catch
@@ -2488,6 +2528,7 @@ public sealed class ChatsController(
                 message.DiscussionMessageId = discussionRootMessage.Id;
             }
 
+            pushDispatchQueue.StageMessages(dbContext, message, discussionRootMessage);
             await dbContext.SaveChangesAsync(cancellationToken);
         }
         catch
@@ -4425,21 +4466,8 @@ public sealed class ChatsController(
 
     private static bool IsMediaAlbumFile(IFormFile file)
     {
-        var normalizedContentType = file.ContentType
+        var contentInfo = AttachmentContentInspector.Inspect(file);
-            ?.Split(';', 2, StringSplitOptions.TrimEntries)
+        return contentInfo.IsImage || contentInfo.IsVideo;
-            .FirstOrDefault()
-            ?.Trim()
-            .ToLowerInvariant();
-        if (!string.IsNullOrWhiteSpace(normalizedContentType) &&
-            (normalizedContentType.StartsWith("image/", StringComparison.Ordinal) ||
-             normalizedContentType.StartsWith("video/", StringComparison.Ordinal)))
-        {
-            return true;
-        }
-
-        var extension = Path.GetExtension(file.FileName).ToLowerInvariant();
-        return extension is ".jpg" or ".jpeg" or ".png" or ".gif" or ".webp" or ".bmp" or
-            ".mp4" or ".m4v" or ".mov" or ".webm" or ".mkv";
     }
 
     private static string? ResolveChannelAuthorSignature(Chat chat, User sender)

src/Ikar.Server/Data/Entities/Entities.cs

@@ -163,6 +163,7 @@ public sealed class Message
     public Chat Chat { get; set; } = null!;
     public Guid SenderId { get; set; }
     public User Sender { get; set; } = null!;
+    public Guid? ClientMessageId { get; set; }
     public string Text { get; set; } = string.Empty;
     public DateTimeOffset SentAt { get; set; } = DateTimeOffset.UtcNow;
     public DateTimeOffset? EditedAt { get; set; }
@@ -229,6 +230,21 @@ public sealed class MessageView
     public DateTimeOffset ViewedAt { get; set; } = DateTimeOffset.UtcNow;
 }
 
+public sealed class PushDispatchOutboxItem
+{
+    public long Id { get; set; }
+    public string DeduplicationKey { get; set; } = string.Empty;
+    public Guid ChatId { get; set; }
+    public Guid MessageId { get; set; }
+    public int Kind { get; set; }
+    public Guid? ActorUserId { get; set; }
+    public string? ReactionEmoji { get; set; }
+    public int AttemptCount { get; set; }
+    public DateTimeOffset NextAttemptAt { get; set; } = DateTimeOffset.UtcNow;
+    public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;
+    public string? LastError { get; set; }
+}
+
 public sealed class PushDevice
 {
     public Guid Id { get; set; } = Guid.NewGuid();

src/Ikar.Server/Data/IkarDbContext.cs

@@ -29,6 +29,7 @@ public sealed class IkarDbContext(DbContextOptions<IkarDbContext> options) : DbC
     public DbSet<MessageReaction> MessageReactions => Set<MessageReaction>();
     public DbSet<MessageView> MessageViews => Set<MessageView>();
     public DbSet<PushDevice> PushDevices => Set<PushDevice>();
+    public DbSet<PushDispatchOutboxItem> PushDispatchOutbox => Set<PushDispatchOutboxItem>();
     public DbSet<Bot> Bots => Set<Bot>();
     public DbSet<BotCommand> BotCommands => Set<BotCommand>();
     public DbSet<BotUpdate> BotUpdates => Set<BotUpdate>();
@@ -44,6 +45,7 @@ public sealed class IkarDbContext(DbContextOptions<IkarDbContext> options) : DbC
         ConfigureChats(modelBuilder);
         ConfigureMessages(modelBuilder);
         ConfigurePushDevices(modelBuilder);
+        ConfigurePushDispatchOutbox(modelBuilder);
         ConfigureBots(modelBuilder);
         ConfigureModeration(modelBuilder);
         ConfigureStories(modelBuilder);
@@ -246,6 +248,9 @@ public sealed class IkarDbContext(DbContextOptions<IkarDbContext> options) : DbC
             entity.HasKey(x => x.Id);
             entity.HasIndex(x => new { x.ChatId, x.SentAt });
             entity.HasIndex(x => new { x.ChatId, x.SenderId, x.SentAt });
+            entity.HasIndex(x => new { x.SenderId, x.ClientMessageId })
+                .IsUnique()
+                .HasFilter("\"ClientMessageId\" IS NOT NULL");
             entity.HasIndex(x => x.SenderId);
             entity.HasIndex(x => x.ReplyToMessageId);
             entity.HasIndex(x => x.TopicId);
@@ -424,6 +429,20 @@ public sealed class IkarDbContext(DbContextOptions<IkarDbContext> options) : DbC
         });
     }
 
+    private static void ConfigurePushDispatchOutbox(ModelBuilder modelBuilder)
+    {
+        modelBuilder.Entity<PushDispatchOutboxItem>(entity =>
+        {
+            entity.ToTable("PushDispatchOutbox");
+            entity.HasKey(x => x.Id);
+            entity.Property(x => x.Id).ValueGeneratedOnAdd();
+            entity.Property(x => x.DeduplicationKey).IsRequired();
+            entity.HasIndex(x => x.DeduplicationKey).IsUnique();
+            entity.HasIndex(x => new { x.NextAttemptAt, x.Id });
+            entity.HasIndex(x => new { x.MessageId, x.Kind });
+        });
+    }
+
     private static void ConfigureBots(ModelBuilder modelBuilder)
     {
         modelBuilder.Entity<Bot>(entity =>

src/Ikar.Server/Ikar.Server.csproj

@@ -7,9 +7,11 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="10.0.4" />
+    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="10.0.9" />
-    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.4" />
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.9" />
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="10.0.4" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="10.0.9" />
+    <PackageReference Include="Microsoft.OpenApi" Version="2.7.5" />
+    <PackageReference Include="SQLitePCLRaw.bundle_e_sqlite3" Version="3.0.3" />
   </ItemGroup>
 
   <ItemGroup>

src/Ikar.Server/Infrastructure/Auth/EmailAuthChallengeStore.cs

@@ -6,11 +6,17 @@ namespace Ikar.Server.Infrastructure.Auth;
 public sealed class EmailAuthChallengeStore
 {
     private static readonly TimeSpan ChallengeLifetime = TimeSpan.FromMinutes(10);
+    private static readonly TimeSpan MinimumRequestInterval = TimeSpan.FromSeconds(60);
+    private static readonly TimeSpan RequestWindow = TimeSpan.FromMinutes(15);
+    private const int MaxRequestsPerWindow = 5;
+    private const int MaxVerificationAttempts = 5;
     private readonly ConcurrentDictionary<string, EmailAuthChallenge> _challenges = new(StringComparer.Ordinal);
+    private readonly ConcurrentDictionary<string, RequestBucket> _requestBuckets = new(StringComparer.Ordinal);
 
     public EmailAuthChallenge Create(string normalizedEmail, string normalizedPhoneNumber, bool isRegistered)
     {
         CleanupExpired();
+        EnforceRequestLimit($"{normalizedEmail}|{normalizedPhoneNumber}");
 
         var challenge = new EmailAuthChallenge(
             Guid.NewGuid().ToString("N"),
@@ -39,12 +45,21 @@ public sealed class EmailAuthChallengeStore
 
         if (!string.Equals(challenge.NormalizedEmail, normalizedEmail, StringComparison.Ordinal) ||
             !string.Equals(challenge.NormalizedPhoneNumber, normalizedPhoneNumber, StringComparison.Ordinal) ||
-            !string.Equals(challenge.Code, code, StringComparison.Ordinal) ||
             challenge.ExpiresAt <= DateTimeOffset.UtcNow)
         {
             return null;
         }
 
+        if (!string.Equals(challenge.Code, code, StringComparison.Ordinal))
+        {
+            if (challenge.RegisterFailedAttempt() >= MaxVerificationAttempts)
+            {
+                _challenges.TryRemove(challenge.Id, out _);
+            }
+
+            return null;
+        }
+
         _challenges.TryRemove(challenge.Id, out _);
         return challenge;
     }
@@ -64,13 +79,74 @@ public sealed class EmailAuthChallengeStore
                 _challenges.TryRemove(pair.Key, out _);
             }
         }
+
+        foreach (var pair in _requestBuckets)
+        {
+            if (now - pair.Value.WindowStartedAt >= RequestWindow)
+            {
+                _requestBuckets.TryRemove(pair.Key, out _);
+            }
+        }
     }
 
-    public sealed record EmailAuthChallenge(
+    private void EnforceRequestLimit(string key)
-        string Id,
+    {
-        string NormalizedEmail,
+        var now = DateTimeOffset.UtcNow;
-        string NormalizedPhoneNumber,
+        var bucket = _requestBuckets.GetOrAdd(key, _ => new RequestBucket(now));
-        string Code,
+        lock (bucket)
-        DateTimeOffset ExpiresAt,
+        {
-        bool IsRegistered);
+            if (now - bucket.WindowStartedAt >= RequestWindow)
+            {
+                bucket.WindowStartedAt = now;
+                bucket.LastRequestedAt = DateTimeOffset.MinValue;
+                bucket.Count = 0;
+            }
+
+            var sinceLastRequest = now - bucket.LastRequestedAt;
+            if (bucket.LastRequestedAt != DateTimeOffset.MinValue && sinceLastRequest < MinimumRequestInterval)
+            {
+                throw new AuthChallengeRateLimitException(MinimumRequestInterval - sinceLastRequest);
+            }
+
+            if (bucket.Count >= MaxRequestsPerWindow)
+            {
+                throw new AuthChallengeRateLimitException(RequestWindow - (now - bucket.WindowStartedAt));
+            }
+
+            bucket.LastRequestedAt = now;
+            bucket.Count++;
+        }
+    }
+
+    public sealed class EmailAuthChallenge(
+        string id,
+        string normalizedEmail,
+        string normalizedPhoneNumber,
+        string code,
+        DateTimeOffset expiresAt,
+        bool isRegistered)
+    {
+        private int _failedAttempts;
+
+        public string Id { get; } = id;
+        public string NormalizedEmail { get; } = normalizedEmail;
+        public string NormalizedPhoneNumber { get; } = normalizedPhoneNumber;
+        public string Code { get; } = code;
+        public DateTimeOffset ExpiresAt { get; } = expiresAt;
+        public bool IsRegistered { get; } = isRegistered;
+
+        public int RegisterFailedAttempt() => Interlocked.Increment(ref _failedAttempts);
+    }
+
+    private sealed class RequestBucket(DateTimeOffset windowStartedAt)
+    {
+        public DateTimeOffset WindowStartedAt { get; set; } = windowStartedAt;
+        public DateTimeOffset LastRequestedAt { get; set; } = DateTimeOffset.MinValue;
+        public int Count { get; set; }
+    }
+}
+
+public sealed class AuthChallengeRateLimitException(TimeSpan retryAfter) : Exception("Authentication challenge rate limit exceeded.")
+{
+    public TimeSpan RetryAfter { get; } = retryAfter;
 }

src/Ikar.Server/Infrastructure/Bots/BotCreatorService.cs

@@ -376,6 +376,7 @@ public sealed class BotCreatorService(
 
         chat.LastActivityAt = now;
         dbContext.Messages.Add(reply);
+        pushDispatchQueue.StageMessages(dbContext, reply);
         await dbContext.SaveChangesAsync(cancellationToken);
 
         var loadedReply = await dbContext.Messages

src/Ikar.Server/Infrastructure/Calls/CallSessionCleanupService.cs

@@ -0,0 +1,40 @@
+using Ikar.Server.Infrastructure.Hubs;
+using Ikar.Shared;
+using Microsoft.AspNetCore.SignalR;
+using Microsoft.Extensions.Options;
+
+namespace Ikar.Server.Infrastructure.Calls;
+
+public sealed class CallSessionCleanupService(
+    CallSessionStore store,
+    IHubContext<MessengerHub> hubContext,
+    IOptions<WebRtcOptions> options,
+    ILogger<CallSessionCleanupService> logger) : BackgroundService
+{
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        using var timer = new PeriodicTimer(TimeSpan.FromSeconds(5));
+        while (await timer.WaitForNextTickAsync(stoppingToken))
+        {
+            var expired = store.DrainExpired(
+                DateTimeOffset.UtcNow,
+                TimeSpan.FromSeconds(Math.Clamp(options.Value.RingingTimeoutSeconds, 15, 300)),
+                TimeSpan.FromHours(Math.Clamp(options.Value.MaximumCallDurationHours, 1, 24)));
+            foreach (var session in expired)
+            {
+                var payload = new CallEndedDto(
+                    session.CallId,
+                    session.ChatId,
+                    session.EndReason,
+                    session.MediaType);
+                await Task.WhenAll(
+                    hubContext.Clients.User(session.CallerId.ToString()).SendAsync("CallEnded", payload, stoppingToken),
+                    hubContext.Clients.User(session.CalleeId.ToString()).SendAsync("CallEnded", payload, stoppingToken));
+                logger.LogInformation(
+                    "Expired call session {CallId} with reason {Reason}.",
+                    session.CallId,
+                    session.EndReason);
+            }
+        }
+    }
+}

src/Ikar.Server/Infrastructure/Calls/CallSessionStore.cs

@@ -135,6 +135,29 @@ public sealed class CallSessionStore
         }
     }
 
+    public IReadOnlyList<ActiveCallSession> DrainExpired(
+        DateTimeOffset now,
+        TimeSpan ringingTimeout,
+        TimeSpan maximumConnectedDuration)
+    {
+        lock (_sync)
+        {
+            var expired = _sessions.Values
+                .Where(stored =>
+                    stored.State == CallSessionState.Ringing && stored.CreatedAt.Add(ringingTimeout) <= now ||
+                    stored.State == CallSessionState.Connected &&
+                    stored.ConnectedAt is not null &&
+                    stored.ConnectedAt.Value.Add(maximumConnectedDuration) <= now)
+                .ToList();
+            foreach (var stored in expired)
+            {
+                RemoveSession(stored, stored.State == CallSessionState.Ringing ? "no_answer" : "timeout");
+            }
+
+            return expired.Select(stored => stored.ToSnapshot()).ToList();
+        }
+    }
+
     private bool TryTerminate(Guid callId, Guid userId, string reason, bool requireParticipant, out ActiveCallSession? session, out string error)
     {
         lock (_sync)

src/Ikar.Server/Infrastructure/Calls/WebRtcOptions.cs

@@ -14,6 +14,10 @@ public sealed class WebRtcOptions
         }
     ];
 
+    public int RingingTimeoutSeconds { get; set; } = 60;
+
+    public int MaximumCallDurationHours { get; set; } = 8;
+
     public IReadOnlyList<CallIceServerDto> ToDto() =>
         IceServers
             .Where(server => server.Urls.Count > 0)

src/Ikar.Server/Infrastructure/DtoMapper.cs

@@ -130,7 +130,8 @@ public static class DtoMapper
             viewCount,
             BuildStoryReplyDto(message),
             message.DiscussionMessageId,
-            commentCount);
+            commentCount,
+            message.ClientMessageId);
     }
 
     public static AttachmentDto ToDto(this MessageAttachment attachment, Guid chatId) =>

src/Ikar.Server/Infrastructure/Push/PushDispatchBackgroundService.cs

@@ -9,26 +9,52 @@ public sealed class PushDispatchBackgroundService(
     ILogger<PushDispatchBackgroundService> logger) : BackgroundService
 {
     protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        if (!queue.IsDurable)
+        {
+            await ProcessFallbackQueueAsync(stoppingToken);
+            return;
+        }
+
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            var batch = await queue.LoadDueBatchAsync(stoppingToken);
+            if (batch.Count == 0)
+            {
+                await queue.WaitForWorkAsync(stoppingToken);
+                continue;
+            }
+
+            foreach (var workItem in batch)
+            {
+                try
+                {
+                    await ProcessAsync(workItem, stoppingToken);
+                    await queue.CompleteAsync(workItem.OutboxId!.Value, stoppingToken);
+                }
+                catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
+                {
+                    return;
+                }
+                catch (Exception ex)
+                {
+                    logger.LogWarning(
+                        ex,
+                        "Background push dispatch failed for chat {ChatId}, message {MessageId}, kind {Kind}.",
+                        workItem.ChatId,
+                        workItem.MessageId,
+                        workItem.Kind);
+                    await queue.RescheduleAsync(workItem.OutboxId!.Value, ex, stoppingToken);
+                }
+            }
+        }
+    }
+
+    private async Task ProcessFallbackQueueAsync(CancellationToken stoppingToken)
     {
         await foreach (var workItem in queue.ReadAllAsync(stoppingToken))
         {
-            try
+            await ProcessAsync(workItem, stoppingToken);
-            {
-                await ProcessAsync(workItem, stoppingToken);
-            }
-            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
-            {
-                break;
-            }
-            catch (Exception ex)
-            {
-                logger.LogWarning(
-                    ex,
-                    "Background push dispatch failed for chat {ChatId}, message {MessageId}, kind {Kind}.",
-                    workItem.ChatId,
-                    workItem.MessageId,
-                    workItem.Kind);
-            }
         }
     }
 
@@ -43,7 +69,6 @@ public sealed class PushDispatchBackgroundService(
             .SingleOrDefaultAsync(x => x.Id == workItem.ChatId, cancellationToken);
         if (chat is null)
         {
-            logger.LogDebug("Skipping push dispatch because chat {ChatId} was not found.", workItem.ChatId);
             return;
         }
 
@@ -51,15 +76,10 @@ public sealed class PushDispatchBackgroundService(
             .Include(x => x.Sender)
             .Include(x => x.Attachments)
             .SingleOrDefaultAsync(
-                x => x.Id == workItem.MessageId &&
+                x => x.Id == workItem.MessageId && x.ChatId == workItem.ChatId,
-                     x.ChatId == workItem.ChatId,
                 cancellationToken);
         if (message is null)
         {
-            logger.LogDebug(
-                "Skipping push dispatch because message {MessageId} for chat {ChatId} was not found.",
-                workItem.MessageId,
-                workItem.ChatId);
             return;
         }
 
@@ -67,9 +87,6 @@ public sealed class PushDispatchBackgroundService(
         {
             if (workItem.ActorUserId is null || string.IsNullOrWhiteSpace(workItem.ReactionEmoji))
             {
-                logger.LogDebug(
-                    "Skipping reaction push dispatch for message {MessageId} because actor or emoji is missing.",
-                    workItem.MessageId);
                 return;
             }
 
@@ -77,9 +94,6 @@ public sealed class PushDispatchBackgroundService(
                 .SingleOrDefaultAsync(x => x.Id == workItem.ActorUserId.Value, cancellationToken);
             if (reactor is null)
             {
-                logger.LogDebug(
-                    "Skipping reaction push dispatch because reactor {UserId} was not found.",
-                    workItem.ActorUserId.Value);
                 return;
             }
 

src/Ikar.Server/Infrastructure/Push/PushDispatchQueue.cs

@@ -1,4 +1,7 @@
 using System.Threading.Channels;
+using Ikar.Server.Data;
+using Ikar.Server.Data.Entities;
+using Microsoft.EntityFrameworkCore;
 
 namespace Ikar.Server.Infrastructure.Push;
 
@@ -13,19 +16,72 @@ public sealed record PushDispatchWorkItem(
     Guid MessageId,
     PushDispatchKind Kind = PushDispatchKind.ChatMessage,
     Guid? ActorUserId = null,
-    string? ReactionEmoji = null);
+    string? ReactionEmoji = null,
+    long? OutboxId = null);
 
-public sealed class PushDispatchQueue
+public sealed class PushDispatchQueue(IServiceScopeFactory? serviceScopeFactory = null)
 {
-    private readonly Channel<PushDispatchWorkItem> _channel = Channel.CreateUnbounded<PushDispatchWorkItem>(
+    private const int BatchSize = 50;
-        new UnboundedChannelOptions
+    private readonly Channel<PushDispatchWorkItem> _fallbackChannel =
+        Channel.CreateUnbounded<PushDispatchWorkItem>(new UnboundedChannelOptions
         {
             SingleReader = true,
             SingleWriter = false
         });
+    private readonly Channel<bool> _wakeSignals = Channel.CreateBounded<bool>(
+        new BoundedChannelOptions(1)
+        {
+            SingleReader = true,
+            SingleWriter = false,
+            FullMode = BoundedChannelFullMode.DropOldest
+        });
+
+    public bool IsDurable => serviceScopeFactory is not null;
+
+    public void StageMessages(IkarDbContext dbContext, params Message?[] messages)
+    {
+        if (!IsDurable)
+        {
+            return;
+        }
+
+        foreach (var message in messages.Where(message => message is not null).Cast<Message>())
+        {
+            StageWorkItem(
+                dbContext,
+                new PushDispatchWorkItem(message.ChatId, message.Id),
+                $"message:{message.Id:D}");
+        }
+    }
+
+    public void StageReaction(
+        IkarDbContext dbContext,
+        Guid chatId,
+        Guid messageId,
+        Guid reactorUserId,
+        string emoji)
+    {
+        if (!IsDurable)
+        {
+            return;
+        }
+
+        StageWorkItem(
+            dbContext,
+            new PushDispatchWorkItem(
+                chatId,
+                messageId,
+                PushDispatchKind.MessageReaction,
+                reactorUserId,
+                emoji),
+            $"reaction:{messageId:D}:{reactorUserId:D}:{emoji}");
+    }
 
     public ValueTask EnqueueAsync(Guid chatId, Guid messageId, CancellationToken cancellationToken = default) =>
-        _channel.Writer.WriteAsync(new PushDispatchWorkItem(chatId, messageId), cancellationToken);
+        EnqueueWorkItemAsync(
+            new PushDispatchWorkItem(chatId, messageId),
+            $"message:{messageId:D}",
+            cancellationToken);
 
     public ValueTask EnqueueReactionAsync(
         Guid chatId,
@@ -33,15 +89,166 @@ public sealed class PushDispatchQueue
         Guid reactorUserId,
         string emoji,
         CancellationToken cancellationToken = default) =>
-        _channel.Writer.WriteAsync(
+        EnqueueWorkItemAsync(
             new PushDispatchWorkItem(
                 chatId,
                 messageId,
                 PushDispatchKind.MessageReaction,
                 reactorUserId,
                 emoji),
+            $"reaction:{messageId:D}:{reactorUserId:D}:{emoji}",
             cancellationToken);
 
     public IAsyncEnumerable<PushDispatchWorkItem> ReadAllAsync(CancellationToken cancellationToken) =>
-        _channel.Reader.ReadAllAsync(cancellationToken);
+        _fallbackChannel.Reader.ReadAllAsync(cancellationToken);
+
+    public async Task<IReadOnlyList<PushDispatchWorkItem>> LoadDueBatchAsync(CancellationToken cancellationToken)
+    {
+        if (serviceScopeFactory is null)
+        {
+            return [];
+        }
+
+        await using var scope = serviceScopeFactory.CreateAsyncScope();
+        var dbContext = scope.ServiceProvider.GetRequiredService<IkarDbContext>();
+        var now = DateTimeOffset.UtcNow;
+        return await dbContext.PushDispatchOutbox
+            .AsNoTracking()
+            .Where(item => item.NextAttemptAt <= now)
+            .OrderBy(item => item.Id)
+            .Take(BatchSize)
+            .Select(item => new PushDispatchWorkItem(
+                item.ChatId,
+                item.MessageId,
+                (PushDispatchKind)item.Kind,
+                item.ActorUserId,
+                item.ReactionEmoji,
+                item.Id))
+            .ToListAsync(cancellationToken);
+    }
+
+    public async Task CompleteAsync(long outboxId, CancellationToken cancellationToken)
+    {
+        if (serviceScopeFactory is null)
+        {
+            return;
+        }
+
+        await using var scope = serviceScopeFactory.CreateAsyncScope();
+        var dbContext = scope.ServiceProvider.GetRequiredService<IkarDbContext>();
+        await dbContext.PushDispatchOutbox
+            .Where(item => item.Id == outboxId)
+            .ExecuteDeleteAsync(cancellationToken);
+    }
+
+    public async Task RescheduleAsync(long outboxId, Exception error, CancellationToken cancellationToken)
+    {
+        if (serviceScopeFactory is null)
+        {
+            return;
+        }
+
+        await using var scope = serviceScopeFactory.CreateAsyncScope();
+        var dbContext = scope.ServiceProvider.GetRequiredService<IkarDbContext>();
+        var item = await dbContext.PushDispatchOutbox.SingleOrDefaultAsync(x => x.Id == outboxId, cancellationToken);
+        if (item is null)
+        {
+            return;
+        }
+
+        item.AttemptCount++;
+        var delaySeconds = Math.Min(900, 5 * (1 << Math.Min(item.AttemptCount, 8)));
+        item.NextAttemptAt = DateTimeOffset.UtcNow.AddSeconds(delaySeconds);
+        item.LastError = error.Message[..Math.Min(error.Message.Length, 1000)];
+        await dbContext.SaveChangesAsync(cancellationToken);
+    }
+
+    public async Task<int> CountPendingAsync(CancellationToken cancellationToken = default)
+    {
+        if (serviceScopeFactory is null)
+        {
+            return 0;
+        }
+
+        await using var scope = serviceScopeFactory.CreateAsyncScope();
+        return await scope.ServiceProvider.GetRequiredService<IkarDbContext>()
+            .PushDispatchOutbox.CountAsync(cancellationToken);
+    }
+
+    public async Task WaitForWorkAsync(CancellationToken cancellationToken)
+    {
+        using var timeout = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+        timeout.CancelAfter(TimeSpan.FromSeconds(5));
+        try
+        {
+            await _wakeSignals.Reader.ReadAsync(timeout.Token);
+        }
+        catch (OperationCanceledException) when (!cancellationToken.IsCancellationRequested)
+        {
+        }
+    }
+
+    private async ValueTask EnqueueWorkItemAsync(
+        PushDispatchWorkItem workItem,
+        string deduplicationKey,
+        CancellationToken cancellationToken)
+    {
+        if (serviceScopeFactory is null)
+        {
+            await _fallbackChannel.Writer.WriteAsync(workItem, cancellationToken);
+            return;
+        }
+
+        await using var scope = serviceScopeFactory.CreateAsyncScope();
+        var dbContext = scope.ServiceProvider.GetRequiredService<IkarDbContext>();
+        dbContext.PushDispatchOutbox.Add(new PushDispatchOutboxItem
+        {
+            DeduplicationKey = deduplicationKey,
+            ChatId = workItem.ChatId,
+            MessageId = workItem.MessageId,
+            Kind = (int)workItem.Kind,
+            ActorUserId = workItem.ActorUserId,
+            ReactionEmoji = workItem.ReactionEmoji
+        });
+        try
+        {
+            await dbContext.SaveChangesAsync(cancellationToken);
+        }
+        catch (DbUpdateException)
+        {
+            dbContext.ChangeTracker.Clear();
+            if (await dbContext.PushDispatchOutbox
+                .AsNoTracking()
+                .AnyAsync(item => item.DeduplicationKey == deduplicationKey, cancellationToken))
+            {
+                _wakeSignals.Writer.TryWrite(true);
+                return;
+            }
+
+            throw;
+        }
+
+        _wakeSignals.Writer.TryWrite(true);
+    }
+
+    private static void StageWorkItem(
+        IkarDbContext dbContext,
+        PushDispatchWorkItem workItem,
+        string deduplicationKey)
+    {
+        if (dbContext.PushDispatchOutbox.Local.Any(item => item.DeduplicationKey == deduplicationKey))
+        {
+            return;
+        }
+
+        dbContext.PushDispatchOutbox.Add(new PushDispatchOutboxItem
+        {
+            DeduplicationKey = deduplicationKey,
+            ChatId = workItem.ChatId,
+            MessageId = workItem.MessageId,
+            Kind = (int)workItem.Kind,
+            ActorUserId = workItem.ActorUserId,
+            ReactionEmoji = workItem.ReactionEmoji
+        });
+    }
 }

src/Ikar.Server/Infrastructure/Push/PushNotificationDispatcher.cs

@@ -67,6 +67,7 @@ public sealed class PushNotificationDispatcher(
         catch (Exception ex)
         {
             logger.LogWarning(ex, "Push dispatch failed for message {MessageId}.", message.Id);
+            throw;
         }
     }
 
@@ -123,6 +124,7 @@ public sealed class PushNotificationDispatcher(
                 ex,
                 "Push dispatch failed for reaction to message {MessageId}.",
                 message.Id);
+            throw;
         }
     }
 

src/Ikar.Server/Infrastructure/Storage/AttachmentContentInspector.cs

@@ -0,0 +1,30 @@
+namespace Ikar.Server.Infrastructure.Storage;
+
+public sealed record AttachmentContentInfo(string ContentType, bool IsImage, bool IsVideo);
+
+public static class AttachmentContentInspector
+{
+    public static AttachmentContentInfo Inspect(IFormFile file)
+    {
+        Span<byte> header = stackalloc byte[16];
+        using var stream = file.OpenReadStream();
+        var read = stream.Read(header);
+        var bytes = header[..read];
+
+        if (StartsWith(bytes, [0xFF, 0xD8, 0xFF])) return new("image/jpeg", true, false);
+        if (StartsWith(bytes, [0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A])) return new("image/png", true, false);
+        if (StartsWith(bytes, "GIF87a"u8) || StartsWith(bytes, "GIF89a"u8)) return new("image/gif", true, false);
+        if (StartsWith(bytes, "BM"u8)) return new("image/bmp", true, false);
+        if (read >= 12 && StartsWith(bytes, "RIFF"u8) && bytes[8..12].SequenceEqual("WEBP"u8)) return new("image/webp", true, false);
+        if (read >= 8 && bytes[4..8].SequenceEqual("ftyp"u8)) return new("video/mp4", false, true);
+        if (StartsWith(bytes, [0x1A, 0x45, 0xDF, 0xA3])) return new("video/webm", false, true);
+        if (StartsWith(bytes, "OggS"u8)) return new("audio/ogg", false, false);
+        if (StartsWith(bytes, "%PDF-"u8)) return new("application/pdf", false, false);
+        if (StartsWith(bytes, [0x50, 0x4B, 0x03, 0x04])) return new("application/zip", false, false);
+
+        return new("application/octet-stream", false, false);
+    }
+
+    private static bool StartsWith(ReadOnlySpan<byte> bytes, ReadOnlySpan<byte> signature) =>
+        bytes.Length >= signature.Length && bytes[..signature.Length].SequenceEqual(signature);
+}

src/Ikar.Server/Infrastructure/Storage/AttachmentStorageService.cs

@@ -18,6 +18,7 @@ public sealed class AttachmentStorageService(IWebHostEnvironment environment)
         }
 
         var originalFileName = NormalizeOriginalFileName(file.FileName, "attachment");
+        var contentInfo = AttachmentContentInspector.Inspect(file);
         var (attachmentId, physicalPath) = CreateTargetPath(originalFileName);
 
         await using (var source = file.OpenReadStream())
@@ -31,7 +32,7 @@ public sealed class AttachmentStorageService(IWebHostEnvironment environment)
             Id = attachmentId,
             MessageId = messageId,
             OriginalFileName = originalFileName,
-            ContentType = string.IsNullOrWhiteSpace(file.ContentType) ? "application/octet-stream" : file.ContentType,
+            ContentType = contentInfo.ContentType,
             FileSizeBytes = file.Length,
             StoragePath = physicalPath,
             SortOrder = sortOrder,
@@ -51,6 +52,7 @@ public sealed class AttachmentStorageService(IWebHostEnvironment environment)
         }
 
         var originalFileName = NormalizeOriginalFileName(file.FileName, "story-attachment");
+        var contentInfo = AttachmentContentInspector.Inspect(file);
         var (attachmentId, physicalPath) = CreateTargetPath(originalFileName);
 
         await using (var source = file.OpenReadStream())
@@ -64,7 +66,7 @@ public sealed class AttachmentStorageService(IWebHostEnvironment environment)
             Id = attachmentId,
             StoryId = storyId,
             OriginalFileName = originalFileName,
-            ContentType = string.IsNullOrWhiteSpace(file.ContentType) ? "application/octet-stream" : file.ContentType,
+            ContentType = contentInfo.ContentType,
             FileSizeBytes = file.Length,
             StoragePath = physicalPath,
             SortOrder = sortOrder,

src/Ikar.Server/Infrastructure/Storage/DatabaseSchemaBootstrapper.cs

@@ -11,6 +11,7 @@ public sealed class DatabaseSchemaBootstrapper(IkarDbContext dbContext)
         await EnableWriteAheadLoggingAsync(cancellationToken);
         await EnsureMessageAttachmentsTableAsync(cancellationToken);
         await EnsurePushDevicesTableAsync(cancellationToken);
+        await EnsurePushDispatchOutboxTableAsync(cancellationToken);
         await EnsureUserPrivacySettingsTableAsync(cancellationToken);
         await EnsureChatInviteLinksTableAsync(cancellationToken);
         await EnsureChatJoinRequestsTableAsync(cancellationToken);
@@ -67,6 +68,8 @@ public sealed class DatabaseSchemaBootstrapper(IkarDbContext dbContext)
         await EnsureColumnAsync("Messages", "StoryReplyAttachmentKind", "TEXT NULL", cancellationToken);
         await EnsureColumnAsync("Messages", "DiscussionMessageId", "TEXT NULL", cancellationToken);
         await EnsureColumnAsync("Messages", "CommentCount", "INTEGER NOT NULL DEFAULT 0", cancellationToken);
+        await EnsureColumnAsync("Messages", "ClientMessageId", "TEXT NULL", cancellationToken);
+        await EnsureMessagesClientMessageIdIndexAsync(cancellationToken);
         await EnsureLegacyChannelPostsMarkedAsync(cancellationToken);
         await EnsureColumnAsync("MessageAttachments", "SortOrder", "INTEGER NOT NULL DEFAULT 0", cancellationToken);
         await EnsureColumnAsync("MessageAttachments", "Kind", "INTEGER NOT NULL DEFAULT 1", cancellationToken);
@@ -729,6 +732,56 @@ public sealed class DatabaseSchemaBootstrapper(IkarDbContext dbContext)
             cancellationToken);
     }
 
+    private async Task EnsurePushDispatchOutboxTableAsync(CancellationToken cancellationToken)
+    {
+        await dbContext.Database.ExecuteSqlRawAsync(
+            """
+            CREATE TABLE IF NOT EXISTS "PushDispatchOutbox" (
+                "Id" INTEGER NOT NULL CONSTRAINT "PK_PushDispatchOutbox" PRIMARY KEY AUTOINCREMENT,
+                "DeduplicationKey" TEXT NOT NULL,
+                "ChatId" TEXT NOT NULL,
+                "MessageId" TEXT NOT NULL,
+                "Kind" INTEGER NOT NULL,
+                "ActorUserId" TEXT NULL,
+                "ReactionEmoji" TEXT NULL,
+                "AttemptCount" INTEGER NOT NULL DEFAULT 0,
+                "NextAttemptAt" TEXT NOT NULL,
+                "CreatedAt" TEXT NOT NULL,
+                "LastError" TEXT NULL
+            );
+            """,
+            cancellationToken);
+        await dbContext.Database.ExecuteSqlRawAsync(
+            """
+            CREATE UNIQUE INDEX IF NOT EXISTS "IX_PushDispatchOutbox_DeduplicationKey"
+            ON "PushDispatchOutbox" ("DeduplicationKey");
+            """,
+            cancellationToken);
+        await dbContext.Database.ExecuteSqlRawAsync(
+            """
+            CREATE INDEX IF NOT EXISTS "IX_PushDispatchOutbox_NextAttemptAt_Id"
+            ON "PushDispatchOutbox" ("NextAttemptAt", "Id");
+            """,
+            cancellationToken);
+        await dbContext.Database.ExecuteSqlRawAsync(
+            """
+            CREATE INDEX IF NOT EXISTS "IX_PushDispatchOutbox_MessageId_Kind"
+            ON "PushDispatchOutbox" ("MessageId", "Kind");
+            """,
+            cancellationToken);
+    }
+
+    private async Task EnsureMessagesClientMessageIdIndexAsync(CancellationToken cancellationToken)
+    {
+        await dbContext.Database.ExecuteSqlRawAsync(
+            """
+            CREATE UNIQUE INDEX IF NOT EXISTS "IX_Messages_SenderId_ClientMessageId"
+            ON "Messages" ("SenderId", "ClientMessageId")
+            WHERE "ClientMessageId" IS NOT NULL;
+            """,
+            cancellationToken);
+    }
+
     private async Task EnsureColumnAsync(
         string tableName,
         string columnName,

src/Ikar.Server/Program.cs

@@ -3,6 +3,7 @@ using System.Security.Claims;
 using Microsoft.AspNetCore.Authentication.JwtBearer;
 using Microsoft.AspNetCore.Authentication.Cookies;
 using Microsoft.AspNetCore.HttpOverrides;
+using Microsoft.Data.Sqlite;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.IdentityModel.Tokens;
 using Ikar.Server.Data;
@@ -35,8 +36,15 @@ builder.Services.AddEndpointsApiExplorer();
 builder.Services.AddHttpClient();
 
 builder.Services.AddDbContext<IkarDbContext>(options =>
-    options.UseSqlite(builder.Configuration.GetConnectionString("IkarDb") ??
+{
-                      "Data Source=Data/ikar.db"));
+    var configuredConnectionString = builder.Configuration.GetConnectionString("IkarDb") ??
+                                     "Data Source=Data/ikar.db";
+    var connectionString = new SqliteConnectionStringBuilder(configuredConnectionString)
+    {
+        DefaultTimeout = 30
+    }.ToString();
+    options.UseSqlite(connectionString, sqliteOptions => sqliteOptions.CommandTimeout(30));
+});
 
 builder.Services.Configure<ForwardedHeadersOptions>(options =>
 {
@@ -165,10 +173,10 @@ builder.Services.AddAuthorization(options =>
 });
 builder.Services.AddSingleton<PresenceTracker>();
 builder.Services.AddSingleton<CallSessionStore>();
+builder.Services.AddHostedService<CallSessionCleanupService>();
 builder.Services.AddSingleton(new ServerRuntimeState(DateTimeOffset.UtcNow));
 builder.Services.AddScoped<TokenService>();
 builder.Services.AddSingleton<BotTokenService>();
-builder.Services.AddSingleton<PhoneAuthChallengeStore>();
 builder.Services.AddSingleton<EmailAuthChallengeStore>();
 builder.Services.AddScoped<IEmailCodeSender, SmtpEmailCodeSender>();
 builder.Services.AddScoped<DatabaseSeeder>();
@@ -228,6 +236,13 @@ app.Use(async (context, next) =>
 app.UseForwardedHeaders();
 app.UseStaticFiles();
 app.Use(async (context, next) =>
+{
+    context.Response.Headers["X-Content-Type-Options"] = "nosniff";
+    context.Response.Headers["Referrer-Policy"] = "no-referrer";
+    context.Response.Headers["X-Frame-Options"] = "DENY";
+    await next();
+});
+app.Use(async (context, next) =>
 {
     if (!ShouldEnforceAndroidClientVersion(context.Request))
     {
@@ -269,17 +284,62 @@ app.UseMiddleware<ApiRateLimitMiddleware>();
 app.UseAuthorization();
 
 app.MapControllers();
-app.MapGet("/health", async (IkarDbContext dbContext, CancellationToken cancellationToken) =>
+app.MapGet("/health", async (
+    IkarDbContext dbContext,
+    IWebHostEnvironment environment,
+    IConfiguration configuration,
+    PushDispatchQueue pushQueue,
+    CancellationToken cancellationToken) =>
 {
     var canConnect = await dbContext.Database.CanConnectAsync(cancellationToken);
-    return canConnect
+    var dataPath = Path.Combine(environment.ContentRootPath, "Data");
-        ? Results.Ok(new { status = "ok" })
+    var freeDiskBytes = ResolveAvailableDiskSpace(dataPath);
-        : Results.StatusCode(StatusCodes.Status503ServiceUnavailable);
+    var diskHealthy = freeDiskBytes >= 512L * 1024 * 1024;
+    var pendingPushCount = await pushQueue.CountPendingAsync(cancellationToken);
+
+    var backupDirectory = configuration["Backup:Directory"];
+    DateTimeOffset? latestBackupAt = null;
+    if (!string.IsNullOrWhiteSpace(backupDirectory) && Directory.Exists(backupDirectory))
+    {
+        latestBackupAt = Directory.EnumerateFiles(backupDirectory, "ikar-*.tar.gz")
+            .Select(path => new DateTimeOffset(File.GetLastWriteTimeUtc(path), TimeSpan.Zero))
+            .OrderByDescending(value => value)
+            .FirstOrDefault();
+    }
+
+    var backupRequired = configuration.GetValue("Backup:RequireFreshBackup", false);
+    var backupHealthy = !backupRequired ||
+        latestBackupAt is not null && latestBackupAt >= DateTimeOffset.UtcNow.AddHours(-36);
+    var healthy = canConnect && diskHealthy && backupHealthy;
+    var payload = new
+    {
+        status = healthy ? "ok" : "degraded",
+        database = canConnect ? "ok" : "unavailable",
+        disk = diskHealthy ? "ok" : "low",
+        freeDiskBytes,
+        backup = backupHealthy ? "ok" : "stale",
+        latestBackupAt,
+        pendingPushCount
+    };
+    return Results.Json(
+        payload,
+        statusCode: healthy ? StatusCodes.Status200OK : StatusCodes.Status503ServiceUnavailable);
 });
 app.MapHub<MessengerHub>("/hubs/messenger");
 
 app.Run();
 
+static long ResolveAvailableDiskSpace(string path)
+{
+    var fullPath = Path.GetFullPath(path);
+    var drive = DriveInfo.GetDrives()
+        .Where(candidate => fullPath.StartsWith(candidate.Name, StringComparison.Ordinal))
+        .OrderByDescending(candidate => candidate.Name.Length)
+        .FirstOrDefault();
+
+    return drive?.AvailableFreeSpace ?? new DriveInfo(Path.GetPathRoot(fullPath)!).AvailableFreeSpace;
+}
+
 static bool ShouldEnforceAndroidClientVersion(HttpRequest request)
 {
     if (request.Path.StartsWithSegments("/health", StringComparison.OrdinalIgnoreCase) ||

src/Ikar.Server/appsettings.json

@@ -15,6 +15,8 @@
     "ServiceAccountJson": ""
   },
   "WebRtc": {
+    "RingingTimeoutSeconds": 60,
+    "MaximumCallDurationHours": 8,
     "IceServers": [
       {
         "Urls": [

src/Ikar.Shared/MessageContracts.cs

@@ -58,7 +58,8 @@ public sealed record MessageDto(
     int? ViewCount = null,
     StoryReplyDto? StoryReply = null,
     Guid? DiscussionMessageId = null,
-    int? CommentCount = null);
+    int? CommentCount = null,
+    Guid? ClientMessageId = null);
 
 public sealed record SendMessageRequest(
     string Text,
@@ -66,7 +67,8 @@ public sealed record SendMessageRequest(
     Guid? TopicId = null,
     bool? HasProtectedContent = null,
     int? TtlSeconds = null,
-    Guid? StoryReplyStoryId = null);
+    Guid? StoryReplyStoryId = null,
+    Guid? ClientMessageId = null);
 
 public sealed record UpdateMessageRequest(string Text);