[Feature Request] Song Caching

Looking for a caching ability, For repeat songs and playlists.

Hoping to save a local copy of commonly played music to allow for quick re-playing of already played songs.

1. Play a song
2. Play another song
3. Play the previous song without having to download it again.
4. ???
5. Weird pause in-between songs because of slow download speed might be bopped.

Quick edit:
Maybe the automatic downloading of the next song in queue to prepare to help with the delay as well. If at all possible.

**Please check the following links to confirm that your feature has not already been requested:**
I tried searching, Didn't see it.

No source files, tests, or entry points are named. Start by tracing how songs are downloaded and played, then define the cache and queue behavior needed to replay a song without downloading it again, including the proposed next-song prefetch; done means repeat playback avoids the download delay without introducing the reported pause.

Written by the indexing model from the issue text.