fix(android): tear down surviving call legs on empty-metadata restart

If LMK kills only the main process, the Telecom call survives in the
:callkeep_core process (kept alive by the system server binding). The old
unconditional sticky-restart notification accidentally provided the last
hang-up handle for that leg: Hang up on the orphan notification reached
tearDownService. The empty-metadata guard removed that handle silently,
leaving the device stuck in a zombie Telecom call (new incoming calls are
treated as busy/call-waiting) with no UI to end it until the app is reopened.

Call tearDownService() in the guard branch before stopping: the zombie leg is
now cleaned up automatically instead of requiring a manual tap. It must run
before stopForeground - while the service is still foreground, the
startService toward the connection services is exempt from background-start
restrictions (both communicate() implementations are also try/catch-guarded).

Author: SERDUN

webtrit_callkeep_android/android/src/main/kotlin/com/webtrit/callkeep/services/services/active_call/ActiveCallService.kt

@@ -80,7 +80,15 @@ class ActiveCallService : Service() {
             // process was killed. NotificationManager tracks active calls in its own static
             // list, so nothing will ever stop this orphaned instance - an ongoing notification
             // left here would be undismissable until the user force-stops the app.
-            Log.w(TAG, "onStartCommand: no calls metadata (null-intent restart), stopping self")
+            //
+            // A call leg may have survived in :callkeep_core (Telecom keeps that process alive
+            // via its own binding), and this restart is the last signal the main process gets
+            // about it: tear the connection services down so the device is not left stuck in a
+            // zombie Telecom call with no UI to end it. Must run before stopForeground - while
+            // this service is still foreground the startService toward the connection services
+            // is exempt from background-start restrictions.
+            Log.w(TAG, "onStartCommand: no calls metadata (null-intent restart), tearing down and stopping self")
+            CallkeepCore.instance.tearDownService()
             stopForeground(STOP_FOREGROUND_REMOVE)
             stopSelf()
             return START_NOT_STICKY

webtrit_callkeep_android/android/src/test/kotlin/com/webtrit/callkeep/services/services/active_call/ActiveCallServiceRestartTest.kt

@@ -29,6 +29,7 @@ import org.robolectric.annotation.Config
  * cannot be swiped away, and the Hang up action has no visible effect.
  *
  * The guard: after satisfying the startForeground contract, an instance with no calls
+ * tears down the connection services (a call leg may have survived in :callkeep_core),
  * removes its notification and stops itself; the empty branch of hungUpCall does the same
  * on top of the existing tearDownService fallback.
  */