fix: catch SecurityException when notification access not granted

app/src/main/java/top/yeij/hearth/media/MediaSessionSource.kt

@@ -55,9 +55,19 @@ class MediaSessionSource(context: Context) {
     fun start(cb: (MediaInfo?) -> Unit) {
         stop()
         callback = cb
+        try {
             msm.addOnActiveSessionsChangedListener(activeSessionsListener, listenerComponent)
             registered = true
             Log.d(TAG, "start: media session listener registered")
+        } catch (e: SecurityException) {
+            // 未授权「通知使用权」时系统抛 SecurityException：媒体监听降级为不可用，不崩溃。
+            // 用户在系统设置开启通知使用权后，重启 Hearth 才会恢复媒体卡。
+            // MediaSessionService throws SecurityException without notification access;
+            // degrade to media listening disabled instead of crashing. Media card recovers
+            // after the user grants notification access and restarts Hearth.
+            Log.w(TAG, "start: no notification access, media listener disabled: ${e.message}")
+            registered = false
+        }
     }
 
     // 注销监听：释放回调引用，供 Activity onDestroy 调用