Add an offline cached symbol for downloaded albums/playlists

Feature description:

There is already the ability to see additional information about tracks, one of these being whether they’re offline cached. What would be nice is the option to also do this for albums and/or playlists that have been fully downloaded (i.e. every track in them has been offline cached)

Brought benefits:

It could possibly make it more obvious which albums/playlists have been downloaded, without having to explicitly filter your library to “available offline”. This may be especially useful in large libraries with lots of albums for example

Other application solutions:

Both Spotify and Tidal have appropriate icons next to albums that have been fully downloaded when viewing your albums. I’m not sure whether this is also the case for playlists, however, but if it is then it wouldn’t look too dissimilar