feat: the Wanted view becomes Collection, shaped like Lidarr: an artist catalogue first, the state sections down a left rail (M502 #5577)

The section opens on a catalogue of every artist on the list, A–Z with a
letter rail, each card showing how many of their albums are held. An artist
opens on their page: every album of theirs, held or not, with its status,
search, releases and tracks. Wanted, Missing files, Activity, Following and
Blocked sit down a left rail as the sections that show state; Held is gone,
the catalogue shows it. The section moves from /wanted to /collection.

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

web/src/lib/components/ReacquisitionSettingsCard.svelte

@@ -74,7 +74,7 @@
     <h3 class="font-display text-lg font-medium text-text-primary">Automatic re-acquisition</h3>
     <p class="mt-1 text-sm text-text-secondary">
       When a file has been missing for a while, Minstrel can put its album back on the
-      <a href="/wanted/missing" class="text-accent-fg hover:underline">wanted list</a>
+      <a href="/collection/missing" class="text-accent-fg hover:underline">wanted list</a>
       by itself. It's wanted per album, not per track: a whole folder going missing is one
       want, not forty.
     </p>