Simpler APIs (#28)

* TrackSource

* remove absolute import

* typo

* get track

* set source enabled

* fix symbol collision

* move to participant

* update proto

* screen share audio

* typo

* format

* change screen share name

lib/src/track/track.dart

@@ -9,6 +9,7 @@ import '../logger.dart';
 import '../managers/event.dart';
 import '../proto/livekit_models.pb.dart' as lk_models;
 import '../support/disposable.dart';
+import '../types.dart';
 
 /// Wrapper around a MediaStreamTrack with additional metadata.
 /// Base for [AudioTrack] and [VideoTrack],
@@ -17,10 +18,11 @@ abstract class Track extends DisposableChangeNotifier
     with EventsEmittable<TrackEvent> {
   static const uuid = Uuid();
   static const cameraName = 'camera';
-  static const screenShareName = 'screen';
+  static const screenShareName = 'screenshare';
 
   final String name;
   final lk_models.TrackType kind;
+  final TrackSource source;
   rtc.MediaStreamTrack mediaStreamTrack;
 
   String? sid;
@@ -33,6 +35,7 @@ abstract class Track extends DisposableChangeNotifier
 
   Track(
     this.kind,
+    this.source,
     this.name,
     this.mediaStreamTrack,
   ) {