/music?path=<rel> replaces the music:cwd channel. Each panel reads the param
itself through useMusicCwd(), so MusicBrowser, MusicDetail and FavoritesView
no longer tell each other where they are, and every drill-in is a <Link>:
library rows, folder rows, album/artist cards, both "up" affordances, the
favorites rows, and the dock's now-playing tile. Track rows stay buttons —
they play, which is a mutation.
A query param rather than a nested route because the location is only one of
the things this screen holds (the lyrics split and the favorites view are the
others), and a splat has to be a route's last segment.
MusicPlayerHost is mounted outside <Routes> and used to write the channel and
then navigate('/music') to make the write visible — the audit's only
navigate-with-a-side-effect. That collapses to one <Link>.
music:resync (a refresh signal) and music:favorites (a view of one panel) stay
channels, deliberately.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>