Expose playlist metadata in playlist response object

[Drapersniper]

Exposing things such as type, url, author, artwork for sources that support it would be a really nice addition.

Lavascr already does a this for it's playlists inside the pluginInfo object but it would be nice seeing a more wide support for all sources natively.

[Walkyst]

Did you check readme? You can use custom branch for artworks

[Drapersniper]

This is explicitly for Playlists objects, not the tracks; currently, the artwork is exposed only to Tracks, I was talking to @TopiSenpai about it, and they asked me to open a tracking issue for it.

[topi314]

The idea is to extend the current AudioPlaylist interface with new fields like
url
type (playlist, album, top tracks, etc)
artworkUrl

These fields would all be nullable

this change could be done backwards compatible via default methods in the interface

[Walkyst]

url and artworkUrl shouldn't be a problem but not sure about type and it's purpose

[topi314]

sources like spotify, deezer & co don't only have playlists, but also albumns
having that metadata somewhere would be nice so you can say Loaded Album x, Loaded Top Songs x instead of Loaded Playlist x for everything

playlist author would also be interesting to output