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/search.svg

@@ -1 +1,3 @@
-<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.65" stroke-linecap="round" stroke-linejoin="round" class="lucide lucide-search" xmlns="http://www.w3.org/2000/svg" width="128" height="128" color="#fff"><circle cx="11" cy="11" r="8"></circle><path d="m21 21-4.3-4.3"></path></svg>
+<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="M10 1C5.02944 1 1 5.02944 1 10C1 14.9706 5.02944 19 10 19C12.125 19 14.078 18.2635 15.6177 17.0319L20.2929 21.7071C20.6834 22.0976 21.3166 22.0976 21.7071 21.7071C22.0976 21.3166 22.0976 20.6834 21.7071 20.2929L17.0319 15.6177C18.2635 14.078 19 12.125 19 10C19 5.02944 14.9706 1 10 1ZM3 10C3 6.13401 6.13401 3 10 3C13.866 3 17 6.13401 17 10C17 13.866 13.866 17 10 17C6.13401 17 3 13.866 3 10Z" fill="currentColor"/>
+</svg>