Prepare QSfera production release

Android/qsferaApp/build.gradle

@@ -14,6 +14,18 @@ def envValue(String primary, String legacy = null) {
     return legacy ? System.getenv(legacy) : null
 }
 
+def releaseSigningEnv = [
+    [primary: 'QSFERA_RELEASE_KEYSTORE', legacy: 'OC_RELEASE_KEYSTORE'],
+    [primary: 'QSFERA_RELEASE_KEYSTORE_PASSWORD', legacy: 'OC_RELEASE_KEYSTORE_PASSWORD'],
+    [primary: 'QSFERA_RELEASE_KEY_ALIAS', legacy: 'OC_RELEASE_KEY_ALIAS'],
+    [primary: 'QSFERA_RELEASE_KEY_PASSWORD', legacy: 'OC_RELEASE_KEY_PASSWORD'],
+]
+
+def missingReleaseSigningEnvKeys = {
+    releaseSigningEnv.findAll { !envValue(it.primary, it.legacy) }
+        .collect { "${it.primary} (${it.legacy} legacy fallback)" }
+}
+
 dependencies {
     // Data and domain modules
     implementation project(':qsferaDomain')
@@ -123,8 +135,8 @@ android {
 
         testInstrumentationRunner "eu.qsfera.android.utils.OCTestAndroidJUnitRunner"
 
-        versionCode = 32
-        versionName = "1.3.4"
+        versionCode = 34
+        versionName = "1.3.6"
 
         buildConfigField "String", gitRemote, "\"" + getGitOriginRemote() + "\""
         buildConfigField "String", commitSHA1, "\"" + getLatestGitHash() + "\""
@@ -235,6 +247,20 @@ android {
     testNamespace "eu.qsfera.android.test"
 }
 
+gradle.taskGraph.whenReady { taskGraph ->
+    def releaseBuildRequested = taskGraph.allTasks.any { task ->
+        def taskName = task.name.toLowerCase()
+        taskName.endsWith("release") &&
+            (taskName.startsWith("assemble") || taskName.startsWith("bundle") || taskName.startsWith("package"))
+    }
+    def missingSigningEnvKeys = missingReleaseSigningEnvKeys()
+    if (releaseBuildRequested && !missingSigningEnvKeys.isEmpty()) {
+        throw new GradleException(
+            "Release builds must be signed. Missing env vars: ${missingSigningEnvKeys.join(', ')}"
+        )
+    }
+}
+
 // Updates output file names of a given variant to format
 // [appName].[variant.versionName].[QSFERA_BUILD_NUMBER]-[variant.name].apk.
 //