handle room update message (#79)

lib/src/core/room.dart

@@ -52,6 +52,9 @@ class Room extends DisposableChangeNotifier with EventsEmittable<RoomEvent> {
   /// sid of the room
   String? sid;
 
+  /// metadata of the room
+  String? metadata;
+
   /// Server version
   String? get serverVersion => _serverVersion;
   String? _serverVersion;
@@ -202,6 +205,10 @@ class Room extends DisposableChangeNotifier with EventsEmittable<RoomEvent> {
       //
       await publication.updateSubscriptionAllowed(event.allowed);
     })
+    ..on<SignalRoomUpdateEvent>((event) async {
+      metadata = event.room.metadata;
+      events.emit(RoomMetadataChangedEvent(metadata: event.room.metadata));
+    })
     ..on<EngineTrackAddedEvent>((event) async {
       logger.fine('EngineTrackAddedEvent trackSid:${event.track.id}');