Expose last_played field on tracks (#51)

Author: ijc

music_assistant_models/media_items/media_item.py

@@ -206,6 +206,7 @@ class Track(MediaItem):
     media_type: MediaType = MediaType.TRACK
     duration: int = 0
     artists: UniqueList[Artist | ItemMapping] = field(default_factory=UniqueList)
+    last_played: int = 0  # only available for library/database items
     album: Album | ItemMapping | None = None  # required for album tracks
     disc_number: int = 0  # required for album tracks
     track_number: int = 0  # required for album tracks