feat(library): ignore a release (do-not-monitor)

Add MonitoredRelease.ignored (migration add_release_ignored). The monitor's
enqueue_due skips ignored releases, and they drop off the Wanted list —
independent of `monitored`, so auto-monitor-future can't silently re-grab
an album the user chose to ignore.

- Worker enqueue_due: AND NOT mr.ignored.
- /api/releases/[id] PATCH now accepts `ignored`; /api/wanted filters it out;
  artist detail exposes `ignored`.
- UI: Ignore button on Wanted rows; discography shows an "Ignored" badge with
  an Ignore/Un-ignore toggle (monitor + search disabled while ignored).

Worker + web tests added.

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

web/src/app/api/wanted/route.ts

@@ -4,7 +4,7 @@ import { searchReleaseGroup } from "@/lib/musicbrainz";
 
 export async function GET() {
   const items = await prisma.monitoredRelease.findMany({
-    where: { monitored: true, state: { not: "fulfilled" } },
+    where: { monitored: true, ignored: false, state: { not: "fulfilled" } },
     orderBy: [{ lastSearchedAt: { sort: "asc", nulls: "first" } }, { createdAt: "asc" }],
   });
   return Response.json({