fix: navigate back to primary task when leaving permanent call room

When multiple app instances run in separate tasks (e.g. opened via a
notification), leaving a voice/permanent call room previously started a
new ConversationsListActivity on top of the call task instead of
returning to the existing app task. This caused duplicate task stacks.

Now the call task finds the existing primary task (preferring one rooted
at MainActivity) and navigates it to ConversationsListActivity, removes
any stray non-call tasks, and uses finishAndRemoveTask() to fully clean
up the call task. Falls back to launching MainActivity fresh if no
existing task is found.

AI-assistant: Claude Code v2.1.142 (Claude Sonnet 4.6)

Signed-off-by: Marcel Hibbe <dev@mhibbe.de>

Author: mahibi

app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt

@@ -11,6 +11,7 @@ package com.nextcloud.talk.activities
 
 import android.Manifest
 import android.annotation.SuppressLint
+import android.app.ActivityManager
 import android.app.PendingIntent
 import android.app.RemoteAction
 import android.content.BroadcastReceiver
@@ -78,6 +79,7 @@ import com.nextcloud.talk.camera.BackgroundBlurFrameProcessor
 import com.nextcloud.talk.camera.BlurBackgroundViewModel
 import com.nextcloud.talk.camera.BlurBackgroundViewModel.BackgroundBlurOn
 import com.nextcloud.talk.chat.ChatActivity
+import com.nextcloud.talk.callnotification.CallNotificationActivity
 import com.nextcloud.talk.conversationlist.ConversationsListActivity
 import com.nextcloud.talk.data.user.model.User
 import com.nextcloud.talk.databinding.CallActivityBinding
@@ -2049,9 +2051,8 @@ class CallActivity : CallBaseActivity() {
                     }
 
                     if (conversationModel?.checkIfVoiceRoom() == true) {
-                        val intent = Intent(context, ConversationsListActivity::class.java)
-                        startActivity(intent)
-                        finish()
+                        openConversationListInPrimaryTask()
+                        finishAndRemoveTask()
                     } else if (switchToRoomToken.isNotEmpty()) {
                         val intent = Intent(context, ChatActivity::class.java)
                         intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
@@ -2083,6 +2084,54 @@ class CallActivity : CallBaseActivity() {
             })
     }
 
+    private fun openConversationListInPrimaryTask() {
+        val activityManager = getSystemService(Context.ACTIVITY_SERVICE) as? ActivityManager
+        val appTasks = activityManager
+            ?.appTasks
+            ?.filter { appTask -> appTask.taskInfo?.baseActivity?.packageName == packageName }
+            .orEmpty()
+
+        val primaryTask = appTasks.firstOrNull { appTask ->
+            val taskInfo = appTask.taskInfo
+            val baseActivityName = taskInfo?.baseActivity?.className
+            taskInfo != null &&
+                taskInfo.taskId != taskId &&
+                baseActivityName == MainActivity::class.java.name
+        } ?: appTasks.firstOrNull { appTask ->
+            val taskInfo = appTask.taskInfo
+            val baseActivityName = taskInfo?.baseActivity?.className
+            taskInfo != null &&
+                taskInfo.taskId != taskId &&
+                baseActivityName != CallActivity::class.java.name &&
+                baseActivityName != CallNotificationActivity::class.java.name
+        }
+
+        if (primaryTask != null) {
+            val intent = Intent(context, ConversationsListActivity::class.java).apply {
+                addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP or Intent.FLAG_ACTIVITY_SINGLE_TOP)
+            }
+            primaryTask.startActivity(context, intent, null)
+            primaryTask.moveToFront()
+            val primaryTaskId = primaryTask.taskInfo?.taskId
+            appTasks
+                .filter { appTask ->
+                    val taskInfo = appTask.taskInfo
+                    val baseActivityName = taskInfo?.baseActivity?.className
+                    val isCallTask = baseActivityName == CallActivity::class.java.name ||
+                        baseActivityName == CallNotificationActivity::class.java.name
+                    taskInfo != null && !isCallTask && taskInfo.taskId != primaryTaskId && taskInfo.taskId != taskId
+                }
+                .forEach { it.finishAndRemoveTask() }
+        } else {
+            val mainIntent = Intent(context, MainActivity::class.java).apply {
+                action = Intent.ACTION_MAIN
+                addCategory(Intent.CATEGORY_LAUNCHER)
+                addFlags(Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK)
+            }
+            startActivity(mainIntent)
+        }
+    }
+
     private fun startVideoCapture(isPortrait: Boolean) {
         val (width, height) = if (isPortrait) {
             WIDTH_4_TO_3_RATIO to HEIGHT_4_TO_3_RATIO