Request: Add Shuffle/Repeat buttons

First off, awesome web app thank you!

I've been using this to play some of my own playlists, but I would like to be able to shuffle them or repeat tracks. That possible?

Thanks!

The issue requests shuffle and repeat controls for playlists or tracks in the web app. Start by tracing the existing Web Audio API and SoundCloud playback flow, then clarify whether repeat applies to tracks, playlists, or both. Done means the requested controls work consistently for the selected playback scope.

Written by the indexing model from the issue text.