Fix mobile playback state listener leak in AudioPlayer (#13849)

Move `TrackPlayer` PlaybackState listener registration into a managed
`useEffect` with cleanup so we don't leak listeners on each render
during playback. This prevents callback fan-out that can cause
crashes/restarts when the app is backgrounded.

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Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: Ray Jacobson <raymondjacobson@users.noreply.github.com>

Author: 3 people

packages/mobile/src/components/audio/AudioPlayer.tsx

@@ -593,7 +593,16 @@ export const AudioPlayer = () => {
     }
   }, [])
 
-  TrackPlayer.addEventListener(Event.PlaybackState, handlePlayerStateChange)
+  useEffect(() => {
+    const subscription = TrackPlayer.addEventListener(
+      Event.PlaybackState,
+      handlePlayerStateChange
+    )
+
+    return () => {
+      subscription.remove()
+    }
+  }, [handlePlayerStateChange])
 
   // Seek handler
   useEffect(() => {