Redesign media card with album art, 7-button transport, and Wolf Kit icons

Replace media card with full redesign: rectangular album art (180px) with
background fetcher, track title + artist display, volume icon + percentage,
progress bar, and 7-button transport row (playlist, skip-back, seek-back,
play/pause, seek-forward, skip-forward, search) with Apple-style opacity
focus. Add scroll-wheel seek and back-button card mode exit.

Replace all media SVG icons with Wolf Kit Rounded Line icons from SVGRepo
(CC Attribution, author: thewolfkit): play, pause, skip-back, skip-forward,
seek-back, seek-forward, playlist (line-3), search, volume.

Fix vacuum card: add config fallback for custom button cards, expand entity
subscriptions for derived entities, fix clean command segment format, remove
fill, increase image size to 160px.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

assets/ui-icons/playlist.svg

@@ -0,0 +1,5 @@
+<svg width="128" height="128" color="#fff" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M2 6C2 5.44772 2.44772 5 3 5H21C21.5523 5 22 5.44772 22 6C22 6.55228 21.5523 7 21 7H3C2.44772 7 2 6.55228 2 6Z" fill="currentColor"/>
+<path d="M2 12C2 11.4477 2.44772 11 3 11H21C21.5523 11 22 11.4477 22 12C22 12.5523 21.5523 13 21 13H3C2.44772 13 2 12.5523 2 12Z" fill="currentColor"/>
+<path d="M3 17C2.44772 17 2 17.4477 2 18C2 18.5523 2.44772 19 3 19H21C21.5523 19 22 18.5523 22 18C22 17.4477 21.5523 17 21 17H3Z" fill="currentColor"/>
+</svg>