feat(video_calls): repeated calls after call termination fix

lib/features/video_calls/managers/video_call_manager.dart

@@ -406,7 +406,11 @@ class VideoCallManager {
 
   Future<void> endCall() async {
     final uuid = _snapshot.conversationUuid;
-    final shouldNotifyBackend = !_callEndedNotified && uuid.isNotEmpty;
+    final shouldNotifyBackend = shouldNotifyCallEnded(
+      alreadyNotified: _callEndedNotified,
+      hasConversation: uuid.isNotEmpty,
+      peerStillInRoom: _roomHasRemoteUser(),
+    );
     if (uuid.isNotEmpty) {
       _callEndedNotified = true;
     }
@@ -1099,6 +1103,14 @@ class VideoCallManager {
     return false;
   }
 
+  bool _roomHasRemoteUser() {
+    final room = _room;
+    if (room == null) return false;
+    return videoCallRoomStillHasRemoteUser(
+      room.remoteParticipants.values.map((participant) => participant.identity),
+    );
+  }
+
   bool get _canHandleCallAudio =>
       _callStageEntered &&
       !_liveKitDisposed &&

lib/features/video_calls/presentation/bloc/video_call_session/video_call_session_cubit.dart

@@ -541,9 +541,20 @@ class VideoCallSessionCubit extends BaseCubit<VideoCallSessionState> {
   }
 
   Future<void> endCall() async {
-    await _screenWakeLock.release();
-    await _systemPipCoordinator.disarm();
-    await _videoCallManager.endCall();
+    _suppressDisposeSideEffects = true;
+    try {
+      await _screenWakeLock.release();
+      await _systemPipCoordinator.disarm();
+      await _videoCallManager.endCall();
+      if (isClosed) return;
+      // The idle snapshot is ignored while the call screen is still visible,
+      // so hang up has to clear the session before the route pops. Otherwise
+      // dispose keeps the call and the next token request rings both users.
+      emit(const VideoCallSessionState());
+      await _restoreSystemUiAfterCall();
+    } finally {
+      _suppressDisposeSideEffects = false;
+    }
   }
 
   void expandLocal() {

lib/features/video_calls/services/video_call_peer_departure.dart

@@ -18,6 +18,18 @@ bool shouldForceEndCallAfterPeerLeft({
   return !videoCallRoomStillHasRemoteUser(remoteIdentities);
 }
 
+/// The participant who taps hang up must not report the end while the other
+/// person is still in the room. That report and the remaining client's report
+/// both see an empty room and each one rings the other user again.
+bool shouldNotifyCallEnded({
+  required bool alreadyNotified,
+  required bool hasConversation,
+  required bool peerStillInRoom,
+}) {
+  if (!hasConversation || alreadyNotified || peerStillInRoom) return false;
+  return true;
+}
+
 bool shouldForceEndCallAfterRoomDisconnect({
   required bool callStageEntered,
   required bool sessionConnected,