feat(web): one track-list row shape, and drag reorder that snaps (M494, #5393)

Every track list (album, Liked, Search, Search → Tracks, playlist,
History) now draws its rows with TrackListRow inside a TrackList box,
in place of four row components that had drifted apart:

- TrackListRow owns the look: lead column, title over "artist · album",
  like, radio, add to queue, menu, duration, then a trailing slot. It
  also owns the stripe, hover, the now-playing band and the
  unavailable state. The stripe is dropped on now-playing and selected
  rows, where Tailwind would otherwise let `odd:` win.
- TrackRow, PlaylistTrackRow and HistoryRow are wrappers that keep only
  their behaviour: track number and multi-select; grip, remove and
  dead-entry states; cover and timestamp. Playlist and History rows
  gain radio, add and the menu, so every list offers the same actions.
- The radio control is Lucide's Radio icon, not the 📻 emoji.
- Enter on a control inside a row now belongs to that control. The old
  TrackRow played the track when Enter was pressed on "add to queue".
- TrackList has no fill, so the stripe shows on playlists too.

Drag reorder (#5393): neodrag kept the drop offset, so after the list
re-rendered the dragged row sat between two slots. reorderDrag, shared
by the playlist and queue rows:
- snaps the row to whole rows while dragging;
- resets it to its slot on drop;
- on playlists, gives the touch gesture to the grip only, so the list
  still scrolls by touch.
The playlist page reorders optimistically and rolls back on error.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/routes/search/+page.svelte

@@ -5,6 +5,7 @@
   import ArtistCard from '#lib/components/ArtistCard.svelte';
   import AlbumCard from '#lib/components/AlbumCard.svelte';
   import TrackRow from '#lib/components/TrackRow.svelte';
+  import TrackList from '#lib/components/TrackList.svelte';
   import SearchSkeleton from '#lib/components/SearchSkeleton.svelte';
   import ApiErrorBanner from '#lib/components/ApiErrorBanner.svelte';
   import { useDelayed } from '#lib/utils/useDelayed.svelte.js';
@@ -104,11 +105,11 @@
             </a>
           {/if}
         </header>
-        <div class="overflow-hidden rounded border border-border">
+        <TrackList>
           {#each tracks.items as t, i (t.id)}
             <TrackRow tracks={tracks.items} index={i} onPlay={onTrackPlay} />
           {/each}
-        </div>
+        </TrackList>
       </section>
     {/if}
   {/if}