Queue-based playback on top of HTMLAudioElement: rune store + pure
action functions, single <audio> mounted in the root layout driven
via $effect, MediaSession metadata/action handlers, and a persistent
bottom bar with shuffle/repeat/volume. Non-goals: server-side listen
history (awaiting /api/events), cross-refresh persistence, keyboard
shortcuts.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
