Make tracks appears in randomized album order

Instead of just being totally random. Going to have to probably group them or something, shouldn't be too bad.

It'll definitely be PHP.

The issue names no files, tests, or entry points. Start by locating the PHP code that builds the track order, then determine how albums and tracks are represented before choosing a grouping approach. Done means playback is randomized by album while tracks within each album remain together, with the expected behavior covered by verification.

Written by the indexing model from the issue text.