Fix media placeholders and image cache

server/QMax.Api/Controllers/ChatsController.cs

@@ -106,6 +106,7 @@ public sealed class ChatsController(
         }
 
         var messages = (await query.ToArrayAsync(cancellationToken))
+            .Where(message => !IsGenericPreviewPlaceholder(message))
             .OrderByDescending(x => x.SentAt)
             .Take(Math.Clamp(take, 1, 200))
             .ToArray();
@@ -121,6 +122,11 @@ public sealed class ChatsController(
             return;
         }
 
+        if (MessageTextSanitizer.IsGenericMediaLabel(preview))
+        {
+            return;
+        }
+
         var previewAt = chat.LastMessageAt.Value;
         if (chat.HistoryClearedAt is { } historyClearedAt && previewAt <= historyClearedAt)
         {
@@ -202,6 +208,14 @@ public sealed class ChatsController(
         return hash.ToString("x8");
     }
 
+    private static bool IsGenericPreviewPlaceholder(Message message)
+    {
+        return message.Direction == MessageDirection.Incoming &&
+            message.Attachments.Count == 0 &&
+            message.ExternalId?.StartsWith("preview:", StringComparison.Ordinal) == true &&
+            MessageTextSanitizer.IsGenericMediaLabel(message.Text);
+    }
+
     [HttpPost("{chatId:guid}/read")]
     public async Task<IActionResult> MarkRead(Guid chatId, CancellationToken cancellationToken)
     {

server/QMax.Api/Services/MaxBridgeSyncService.cs

@@ -422,7 +422,7 @@ public sealed class MaxBridgeSyncService(
             chat.UnreadCount++;
         }
 
-        var message = shouldNotify
+        var message = shouldNotify && !MessageTextSanitizer.IsGenericMediaLabel(preview)
             ? CreatePreviewMessage(chat, preview, previewAt)
             : null;
         return new ListPreviewApplyResult(true, message);

server/QMax.Api/Services/MessageTextSanitizer.cs

@@ -35,6 +35,8 @@ public static class MessageTextSanitizer
     {
         return value?.Trim().ToLowerInvariant() switch
         {
+            "\u043c\u0435\u0434\u0438\u0430" => true,
+            "media" => true,
             "\u0444\u043e\u0442\u043e" => true,
             "photo" => true,
             "image" => true,