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/seek-forward.svg

@@ -0,0 +1,3 @@
+<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="M3.42091 4.83828C2.43562 4.07194 1 4.77409 1 6.02231V17.9777C1 19.2259 2.43562 19.928 3.42091 19.1617L11.6139 12.7893C11.8575 12.5999 12 12.3086 12 12V17.9777C12 19.2259 13.4356 19.928 14.4209 19.1617L22.6139 12.7893C22.8575 12.5999 23 12.3086 23 12C23 11.6914 22.8575 11.4001 22.6139 11.2106L14.4209 4.83828C13.4356 4.07194 12 4.77409 12 6.02231V12C12 11.6914 11.8575 11.4001 11.6139 11.2106L3.42091 4.83828ZM9.37118 12L3 16.9553V7.04463L9.37118 12ZM20.3712 12L14 16.9553V7.04463L20.3712 12Z" fill="currentColor"/>
+</svg>