feat(web): align the web UI with the design prototype

- Ambient background in the app shell: three drifting blurred blobs,
  the third one tinted with the current track's cover; can be turned off
  in settings and stays still with reduced motion.
- Island player variant (floating glass panel) next to the bar, chosen
  in settings; player source line ("Album · …", "My Wave"), reactions
  around the transport controls, queue drawer.
- Sidebar: like / dislike counters, pending uploads badge on Queue,
  admin Settings page holding the upload queue limits.
- Collection: header tile with kicker, underline tabs, time / number
  lead column with an equalizer for the current track, album column,
  dimmed dislikes with undo, Play all / Shuffle pills.
- Album: cover-tinted header and Play / Shuffle; artist: artist wave,
  Play and popular tracks (new GET /artists/{id}/top-tracks).

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

apps/web/src/app/router.tsx

@@ -11,6 +11,7 @@ import {
 import { AuditPage } from '../pages/admin/AuditPage';
 import { LibraryPage } from '../pages/admin/LibraryPage';
 import { PatternsPage } from '../pages/admin/PatternsPage';
+import { AdminSettingsPage } from '../pages/admin/AdminSettingsPage';
 import { UploadQueuePage } from '../pages/admin/UploadQueuePage';
 import { MyUploadsPage } from '../pages/uploads/MyUploadsPage';
 import { SuggestPage } from '../pages/uploads/SuggestPage';
@@ -224,6 +225,13 @@ const uploadQueueRoute = createRoute({
   component: UploadQueuePage,
 });
 
+const adminSettingsRoute = createRoute({
+  getParentRoute: () => appRoute,
+  path: '/admin/settings',
+  beforeLoad: adminOnly,
+  component: AdminSettingsPage,
+});
+
 const routeTree = rootRoute.addChildren([
   loginRoute,
   setupAdminRoute,
@@ -245,6 +253,7 @@ const routeTree = rootRoute.addChildren([
     suggestRoute,
     myUploadsRoute,
     uploadQueueRoute,
+    adminSettingsRoute,
   ]),
 ]);