Match muted behavior with JS SDK (#32)

* attempt 1

* implement

* clean up

* clean up

* cleaner code

* mute was opposite

* fix suggestion

* fix local pub muted

* update example

* update pubs

* format

lib/src/internal/events.dart

@@ -61,3 +61,13 @@ class TrackVisibilityUpdatedEvent with TrackEvent, InternalEvent {
     required this.info,
   });
 }
+
+@internal
+class TrackMuteUpdatedEvent with TrackEvent, InternalEvent {
+  final Track track;
+  final bool muted;
+  const TrackMuteUpdatedEvent({
+    required this.track,
+    required this.muted,
+  });
+}