fix: stop playback if app is stopped

app/src/main/java/at/lockstep/player/playback/PlaybackService.kt

@@ -62,6 +62,7 @@ class PlaybackService : Service() {
 
     private var queue: List<TrackQueueItem> = emptyList()
     private var index: Int = 0
+    private var tornDown = false
 
     /** Updated on the main thread whenever progress is read from the engine — safe for sensor threads. */
     @Volatile
@@ -524,15 +525,37 @@ class PlaybackService : Service() {
             .build()
     }
 
+    override fun onTaskRemoved(rootIntent: Intent?) {
+        stopPlaybackAndTeardown()
+        stopSelf()
+        super.onTaskRemoved(rootIntent)
+    }
+
     override fun onDestroy() {
+        stopPlaybackAndTeardown()
+        super.onDestroy()
+    }
+
+    /** Stops audio, clears queue state, and removes the foreground notification. Idempotent. */
+    private fun stopPlaybackAndTeardown() {
+        if (tornDown) return
+        tornDown = true
         positionPollJob?.cancel()
+        positionPollJob = null
         positionCachePollJob?.cancel()
+        positionCachePollJob = null
         releaseEngine()
+        queue = emptyList()
+        index = 0
+        cachedPlaybackPositionMs = 0L
+        _uiState.value = PlaybackUiState.initial()
+        if (::mediaSession.isInitialized) {
             mediaSession.run {
                 isActive = false
                 release()
             }
-        super.onDestroy()
+        }
+        stopForeground(STOP_FOREGROUND_REMOVE)
     }
 
     data class PlaybackUiState(