store playcount and duration on the track table

+ allow sorting all items with those two
+ add methods to update scrobble info

app/serializers/album.py

@@ -27,6 +27,7 @@ def serialize_for_card(album: Album):
         "og_title",
         "base_title",
         "genres",
+        "playcount"
     }
 
     return album_serializer(album, props_to_remove)

app/serializers/artist.py

@@ -14,6 +14,7 @@ def serialize_for_card(artist: Artist):
         "trackcount",
         "duration",
         "albumcount",
+        "playcount",
     }
 
     for key in props_to_remove:

app/serializers/track.py

@@ -20,6 +20,7 @@ def serialize_track(track: Track, to_remove: set = {}, remove_disc=True) -> dict
         "artist_hashes",
         "created_date",
         "fav_userids",
+        "playcount",
     }.union(to_remove)
 
     if not remove_disc: