NowPlaying, QuizToolbar and SongControls become their own scenes, the auto
repeat switch moves into the music player scene, and downloading songs moves
into a SongLoader node. The quiz only wires the parts together. Every node
keeps its place on screen.
Screenshots of every UI state are pixel-identical to before, the layout test
still matches the original baseline, and each new part has its own tests.
The quiz (song, playlist, players, music player and the popups opened from
it) moves into Quiz.tscn and the top panel into TopBar.tscn. The main window
keeps only the top bar, the quiz and the popups opened from the top bar, so
other views can be added next to the quiz later. Every node keeps its place
on screen.
Screenshots of every UI state before and after are pixel-identical, and a
layout test checks each node against a baseline taken before the split.
At startup and after resetting the playlist, loading the song list and
preloading the first song started at the same time. When the list
answered last, it cleared the playlist and dropped the preloaded song.
Preloading now starts once the list has loaded, and loading the list is
retried if it fails.
Sansan