Migrate federation settings to preferences
A lot of settings could be handled as preference instead, which would be more flexible and avoid restarting the server for any change:
-
FEDERATION_ENABLED -
FEDERATION_COLLECTION_PAGE_SIZE -
FEDERATION_MUSIC_NEEDS_APPROVAL -
FEDERATION_ACTOR_FETCH_DELAY -
PLAYLISTS_MAX_TRACKS -
API_AUTHENTICATION_REQUIRED