feat(web): cover art on Wanted + Discover album rows

Wanted API returns rgMbid/type/year; Wanted rows show a cover thumb and open
the album modal. Discover suggested-album rows get a cover thumb too. Completes
cover art across the app (artist detail, Library, modals, Wanted, Discover).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/src/app/discover/discover-client.tsx

@@ -5,6 +5,7 @@ import { PageHead } from "../_ui/page-head";
 import { SectionHeader } from "../_ui/section-header";
 import { ArtistModal } from "../_ui/artist-modal";
 import { AlbumModal } from "../_ui/album-modal";
+import { CoverArt } from "../_ui/cover-art";
 
 type Suggestion = {
   id: string;
@@ -189,15 +190,17 @@ export function DiscoverClient() {
           {feed.albums.map((s) => (
             <li key={s.id} className="list-row">
               <div className="main">
-                <div className="rtitle">
-                  <button className="linkish" onClick={() => setAlbumModal(s)}>
-                    {s.album}
-                  </button>{" "}
-                  <span className="artist">· {s.artistName}</span>
-                </div>
-                <div className="rmeta">
-                  <span className="score">score {s.score.toFixed(2)}</span>
-                </div>
+                <button className="disco-open" onClick={() => setAlbumModal(s)} aria-label={`Open ${s.album ?? ""}`}>
+                  <CoverArt rgMbid={s.rgMbid} alt={s.album ?? ""} className="thumb" />
+                  <span>
+                    <span className="rtitle">
+                      {s.album} <span className="artist">· {s.artistName}</span>
+                    </span>
+                    <span className="rmeta">
+                      <span className="score">score {s.score.toFixed(2)}</span>
+                    </span>
+                  </span>
+                </button>
               </div>
               <div className="actions">
                 <button className="btn sm" onClick={() => act(s.id, "want")}>