User profile improvements
Remove usage of SetExclusive
Fix footer button light fading incorrectly
Logic was reliant on HoverLost coming before Hover events, which has since changed. Was also able to tidy this code up a bit in the process.
Also immediately disposes WorkingBeatmaps on ValueChanged.
Fix Player crashing due to null BeatmapInfo (now unused).
Don't start a beatmap's track until the intro is done playing
Make Beatmap non-nullable
Fix crashes related to deleting/importing beatmaps
Fix main menu flashy sides moving too much
Note that tracks' looping is never restored now. There's unfortunately no easy way around this, but it shouldn't have any side-effects for now.