adjust artist by tags to hunt for artist cover

[ZachMyers3]

For #179

Propagate the logic we've used for artist covers into other endpoints. This should cover getArtsits getArtist and ServeSearchThree now as well.

Only displays a cover art tag if we have it locally.

I believe when the rebase took place coverGetPathArtist didn't make it into the merge as well, so I've corrected that.

[ZachMyers3]

Is there anything needed from me? As of right now the nightly branch is non-working for artist-based queries by tags because of the lack of coverGetPathArtist existing in the current branch.

[sentriz]

howdy! thanks for this, I also forgot about the artist view's cover prop.

my thinking about those "spec construct" functions is that they should be thin conversions from the database representation to the subsonic representation of some data. so doing some database lookups in those functions would be a new idea

on top of that, if we need to do this lookup in many places, we should probably store it (similar to your previous pr! 👀)

I added a commit c0ebd26 that stores the guessed artist folder as a column in the artists table. that way the folder can be shared in not only the getArtistInfo lookup as we had already, but also the search3 and getArtists as you suggested 👍

I did some testing myself and it seems to work, please let me know if not

PS sorry I couldn't to a PR review I very little time this week

[sentriz]

PS! for the meantime, the change I added requires at least one track to be touched if it's respective artists cover file has changed

eg

/music/The Fall/artist.png                              # if this was added on its own after the music, then
/music/The Fall/Dragnet (1979)/Psykick Dancehall.flac   # touch this afterwards for above to be picked up

and that's because the artist table is traditionally populated only from audio tags. it would be a bit complicated to change this I think. but let me know if you think it's worth changing

[ZachMyers3]

This all works great! I think the way it's implemented now (seeking a track to populate an artist) works fine the way it is and that was how I was populating covers with my initial implementation as well.

The only thing I noticed is the nightly tag for the docker image doesn't have this commit, but pulling and running locally it worked as expected.

Thanks for the help!