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/pause.svg

@@ -0,0 +1,4 @@
+<svg width="128" height="128" color="#fff" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path fill-rule="evenodd" clip-rule="evenodd" d="M4 5C4 3.89543 4.89543 3 6 3H9C10.1046 3 11 3.89543 11 5V19C11 20.1046 10.1046 21 9 21H6C4.89543 21 4 20.1046 4 19V5ZM9 5H6V19H9V5Z" fill="currentColor"/>
+<path fill-rule="evenodd" clip-rule="evenodd" d="M13 5C13 3.89543 13.8954 3 15 3H18C19.1046 3 20 3.89543 20 5V19C20 20.1046 19.1046 21 18 21H15C13.8954 21 13 20.1046 13 19V5ZM18 5H15V19H18V5Z" fill="currentColor"/>
+</svg>