navidrome/tests/fixtures/listenbrainz.nowplaying.request.json

 {"listen_type": "playing_now", "payload": [{"track_metadata": { "artist_name": "Track Artist", "track_name": "Track Title", "release_name": "Track Album", "additional_info": { "tracknumber": 1, "recording_mbid": "mbz-123", "artist_mbids": ["mbz-789"], "release_mbid": "mbz-456"}}}]}