feat(frontend): render a multi-artist credit as one link per artist

Every artist name in the app went through `artistLink(name, mbid)`, so
a track credited to several artists rendered one link and the rest as
punctuation — "2Pac feat. Snoop Dogg" linked 2Pac and left Snoop Dogg
as text inside it.

`creditLink(parts, fallbackName, fallbackMbid)` renders the credit from
its parts: one link per credited artist, join phrases as plain text
between them. The link boundaries are known by construction, which is
the point — locating a name inside the stored credit string would
reintroduce the mismatch the catalog exists to avoid, since that string
may come from the file's tags while the parts come from MusicBrainz and
the two disagree for ~1 in 3 multi-artist credits.

Fewer than two parts falls through to the previous behaviour exactly,
so a single-artist credit, a file with no recording MBID and a catalog
that has not answered yet all render as they did before. Nothing tries
to split the fallback string: "Simon & Garfunkel" is one artist, which
is why primaryArtist() does not split on "&" either.

The lookup is keyed on the recording MBID, which both sides already
carry — a catalog row has one and so does a local file — so one binding
serves Explore and the library's own lists, and no local table is
needed for this.

credit-store.ts, and three things in it are load-bearing:

- A miss is cached as an empty array. The backend returns nothing for a
  single-artist credit, which is ~87% of tracks, and caching only the
  hits would re-request the rest on every render forever.
- request() is per-row and coalesces into one call per frame. A
  virtualized list cannot hand over "the whole list": 50,000 rows would
  be 100 queries for the ~30 on screen.
- It is an LRU with a counted retainedChars probe, because a cache that
  grows with use is a leak with a schedule.

The virtualized lists push requestUpdate() into the virtualizer rather
than only the host, since its rows come from its own properties — a
host update alone would leave them exactly as they were. now-playing
marks its geometry dirty instead, because the marquee measures the text
it is about to scroll.

track-list keeps the single link while a search term is active: the
highlight spans are computed against the flat credit string, and
mapping them onto decomposed parts is a different problem.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AfVYUVExXsx1nSWrXN8mAh

frontend/src/components/explore-view/explore-view.ts

@@ -16,7 +16,8 @@ import { exploreCache, ARTIST_IMAGE_CACHE_LIMIT } from '../../store/explore-cach
 import { queueStore } from '../../store/queue-store';
 import { notificationStore } from '../../store/notification-store';
 import '../notifications/inline-notice';
-import { artistLink, trackLink, exploreLinkStyles } from '../../utils/explore-link';
+import { creditLink, trackLink, exploreLinkStyles } from '../../utils/explore-link';
+import { creditStore } from '@store/credit-store';
 import { describeError } from '../../utils/describe-error';
 import '@awesome.me/webawesome/dist/components/icon/icon.js';
 import '../library-status-indicator/library-status-indicator.js';
@@ -774,6 +775,14 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
     }
 
     protected override onViewActivate(): void {
+        // A cached primary view, so this is torn down on the way out
+        // rather than on disconnect — which never fires here.
+        this.whileActive(
+            creditStore.subscribe(() => {
+                this.requestUpdate();
+            }),
+        );
+
         // Fetched on arrival rather than on connect: this is a cached
         // primary view, created and warmed at startup, so a fetch there
         // is three catalog queries every user pays for whether or not
@@ -2193,7 +2202,7 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                 <div class="album-title" title="${rg.title}">
                                     ${rg.title}
                                 </div>
-                                <div class="album-artist">${artistLink(rg.artistCredit, rg.artistMbid ?? '')}</div>
+                                <div class="album-artist">${creditLink(creditStore.credits(rg.mbid), rg.artistCredit, rg.artistMbid ?? '')}</div>
                                 <div class="album-meta">
                                     <div class="album-meta-text">
                                         ${rg.primaryType
@@ -2255,7 +2264,7 @@ export class ExploreView extends ViewLifecycleMixin(LitElement) implements Conte
                                         ${trackLink(r.title, r.releaseName ?? '', r.releaseGroupMbid ?? '', r.mbid)}
                                     </div>
                                     <div class="track-artist">
-                                        ${artistLink(r.artistCredit, r.artistMbid ?? '')}
+                                        ${creditLink(creditStore.credits(r.mbid), r.artistCredit, r.artistMbid ?? '')}
                                     </div>
                                 </div>
                                 <div class="track-meta">