fix(library): show album cover art in the Albums grid

The album cards always fell back to the 💿 placeholder: the mapper dropped
the backend's `has_cover` and no album cover URL was ever built. Carry
`hasCover` through `RawAlbum`/`Album` and add `getAlbumCoverUrl` (GET
/albums/{id}/cover, token in the query like the track/stream URLs). The
Library Albums grid and the artist-detail discography now render real
covers, same source the album-detail page already used.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/api/endpoints/streaming.ts

@@ -32,3 +32,18 @@ export function getTrackCoverUrl(
   const base = getApiBaseUrl();
   return `${base}/tracks/${trackId}/cover?token=${encodeURIComponent(token)}`;
 }
+
+/**
+ * Cover image URL for an album, served by `GET /albums/{id}/cover`. Same
+ * `?token=` rationale as the track cover. Returns undefined when the album has
+ * no cover (so callers fall back to generated tile art).
+ */
+export function getAlbumCoverUrl(
+  albumId: string,
+  token: string,
+  hasCover: boolean,
+): string | undefined {
+  if (!hasCover) return undefined;
+  const base = getApiBaseUrl();
+  return `${base}/albums/${albumId}/cover?token=${encodeURIComponent(token)}`;
+}

src/api/mappers.ts

@@ -95,6 +95,7 @@ export interface RawAlbum {
   artist_name: string;
   year: number | null;
   track_count: number;
+  has_cover: boolean;
   created_at: string;
 }
 
@@ -171,7 +172,10 @@ export const toAlbum = (r: RawAlbum): Album => ({
   title: r.title,
   artistId: r.artist_id,
   artistName: r.artist_name,
+  // The album record carries no cover *URL*; `hasCover` says one exists, and the
+  // URL (which needs `?token=`) is built in components via `getAlbumCoverUrl`.
   artUrl: undefined,
+  hasCover: r.has_cover,
   year: r.year ?? undefined,
   trackCount: r.track_count,
   // AlbumOut has no aggregate duration; computed client-side from tracks when

src/api/types.ts

@@ -44,6 +44,8 @@ export interface Album {
   artistId: string;
   artistName: string;
   artUrl?: string;
+  /** Whether the album has cover art served by `GET /albums/{id}/cover`. */
+  hasCover: boolean;
   year?: number;
   trackCount: number;
   totalDurationMs: number;

src/features/artist-detail/ArtistDetailPage.tsx

@@ -20,7 +20,7 @@ import {
 } from '../../store/selectors/localLibrary';
 import { setQueue } from '../../store/slices/queue';
 import { formatDuration } from '../../lib/format';
-import { getCoverUrl } from '../../api/endpoints/streaming';
+import { getCoverUrl, getAlbumCoverUrl } from '../../api/endpoints/streaming';
 import type { Album } from '../../api/types';
 
 export function ArtistDetailPage() {
@@ -251,7 +251,10 @@ export function ArtistDetailPage() {
 
 function AlbumCard({ album, onClick }: { album: Album; onClick: () => void }) {
   const { t } = useTranslation();
-  const artUrl = getCoverUrl(album.artUrl);
+  const token = useAppSelector((s) => s.auth.accessToken);
+  const artUrl =
+    getCoverUrl(album.artUrl) ??
+    (token ? getAlbumCoverUrl(album.id, token, album.hasCover) : undefined);
   return (
     <Card
       onClick={onClick}

src/features/library/LibraryPage.tsx

@@ -28,7 +28,7 @@ import {
 } from '../../store/selectors/localLibrary';
 import { setQueue } from '../../store/slices/queue';
 import type { Track, Album, Artist } from '../../api/types';
-import { getCoverUrl } from '../../api/endpoints/streaming';
+import { getCoverUrl, getAlbumCoverUrl } from '../../api/endpoints/streaming';
 import { formatDuration } from '../../lib/format';
 import { useDebounce } from 'use-debounce';
 
@@ -300,7 +300,12 @@ export function LibraryPage() {
 
 function AlbumCard({ album, onClick }: { album: Album; onClick: () => void }) {
   const { t } = useTranslation();
-  const artUrl = getCoverUrl(album.artUrl);
+  const token = useAppSelector((s) => s.auth.accessToken);
+  // The album record has no cover URL; build one from `hasCover` (served by
+  // GET /albums/{id}/cover, token in the query — <img> can't send a header).
+  const artUrl =
+    getCoverUrl(album.artUrl) ??
+    (token ? getAlbumCoverUrl(album.id, token, album.hasCover) : undefined);
   return (
     <Card
       onClick={onClick}