feat(artist): functional Artist detail screen (§A3)

Replace the scaffold Placeholder with a real artist page wired to the
existing `/artists/{id}` (+ `/albums`, `/tracks`) endpoints: header with
procedural avatar / counts / "Play all" (queues with source=artist),
discography grid (cards → album detail), and the full track list. All
three list states per async section.

Also make the Library artists-tab rows clickable → `/artists/:id`,
closing the previous navigation dead-end.

i18n: new `artist.*` block (en + ru).

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

src/features/artist-detail/ArtistDetailPage.tsx

@@ -1,8 +1,270 @@
+import { useParams, useNavigate } from 'react-router';
 import { useTranslation } from 'react-i18next';
-import { Placeholder } from '../../components/common/Placeholder';
+import { ScrollArea, IconButton, Button, Card } from '@olly/modern-sk';
+import {
+  useGetArtistQuery,
+  useGetArtistAlbumsQuery,
+  useGetArtistTracksQuery,
+} from '../../api/endpoints/library';
+import { TrackRow } from '../../components/track/TrackRow';
+import { ArtTile } from '../../components/common/ArtTile';
+import { LoadingSkeleton } from '../../components/common/LoadingSkeleton';
+import { ErrorState } from '../../components/common/ErrorState';
+import { EmptyState } from '../../components/common/EmptyState';
+import { useAppDispatch } from '../../hooks/useAppDispatch';
+import { setQueue } from '../../store/slices/queue';
+import { formatDuration } from '../../lib/format';
+import { getCoverUrl } from '../../api/endpoints/streaming';
+import type { Album } from '../../api/types';
 
-/** `/artists/:artistId` — A3 artist detail (discography + similar). Scaffold only. */
 export function ArtistDetailPage() {
   const { t } = useTranslation();
-  return <Placeholder title={t('pages.artist')} />;
+  const { artistId } = useParams<{ artistId: string }>();
+  const navigate = useNavigate();
+  const dispatch = useAppDispatch();
+
+  const artistQuery = useGetArtistQuery(artistId ?? '', { skip: !artistId });
+  const albumsQuery = useGetArtistAlbumsQuery(artistId ?? '', {
+    skip: !artistId,
+  });
+  const tracksQuery = useGetArtistTracksQuery(artistId ?? '', {
+    skip: !artistId,
+  });
+
+  if (artistQuery.isLoading) {
+    return (
+      <div style={{ padding: '1.5rem' }}>
+        <LoadingSkeleton rows={10} />
+      </div>
+    );
+  }
+
+  if (artistQuery.isError || !artistQuery.data) {
+    return (
+      <ErrorState
+        message={t('artist.error')}
+        onRetry={() => artistQuery.refetch()}
+      />
+    );
+  }
+
+  const artist = artistQuery.data;
+  const albums = albumsQuery.data ?? [];
+  const tracks = tracksQuery.data ?? [];
+
+  const handlePlayAll = () => {
+    if (!tracks.length) return;
+    dispatch(
+      setQueue({
+        entries: tracks.map((tr) => ({
+          trackId: tr.id,
+          title: tr.title,
+          artistName: tr.artistName,
+          albumTitle: tr.albumTitle,
+          durationMs: tr.durationMs,
+          albumArtUrl: tr.albumArtUrl,
+        })),
+        source: 'artist',
+        sourceId: artist.id,
+        sourceName: artist.name,
+      }),
+    );
+  };
+
+  return (
+    <div style={{ display: 'flex', flexDirection: 'column', height: '100%' }}>
+      <div
+        style={{
+          padding: '1.25rem 1.5rem',
+          borderBottom: '1px solid var(--color-border)',
+          display: 'flex',
+          alignItems: 'center',
+          gap: '1rem',
+          flexShrink: 0,
+        }}
+      >
+        <IconButton
+          variant="ghost"
+          size="sm"
+          onClick={() => navigate(-1)}
+          aria-label={t('common.back')}
+        >
+          ←
+        </IconButton>
+        <div
+          style={{
+            display: 'flex',
+            gap: '1.5rem',
+            alignItems: 'center',
+            flex: 1,
+          }}
+        >
+          <ArtTile seed={artist.id} label={artist.name} size={96} radius={48} />
+          <div>
+            <p
+              style={{
+                margin: 0,
+                fontSize: '0.75rem',
+                color: 'var(--color-text-3)',
+                textTransform: 'uppercase',
+                letterSpacing: '0.05em',
+              }}
+            >
+              {t('artist.type')}
+            </p>
+            <h1
+              style={{
+                margin: '0.25rem 0',
+                fontSize: '1.5rem',
+                fontWeight: 700,
+              }}
+            >
+              {artist.name}
+            </h1>
+            <p
+              style={{
+                margin: 0,
+                color: 'var(--color-text-2)',
+                fontSize: '0.875rem',
+              }}
+            >
+              {t('artist.meta', {
+                albumCount: artist.albumCount,
+                trackCount: artist.trackCount,
+              })}
+            </p>
+          </div>
+        </div>
+        <Button
+          variant="primary"
+          onClick={handlePlayAll}
+          disabled={!tracks.length}
+        >
+          {t('artist.play')}
+        </Button>
+      </div>
+
+      <ScrollArea style={{ flex: 1 }}>
+        {/* Discography */}
+        <section style={{ padding: '1.25rem 1.5rem 0' }}>
+          <h2
+            style={{ margin: '0 0 0.75rem', fontSize: '1rem', fontWeight: 600 }}
+          >
+            {t('artist.albums')}
+          </h2>
+          {albumsQuery.isLoading && <LoadingSkeleton rows={3} height={72} />}
+          {albumsQuery.isError && (
+            <ErrorState onRetry={() => albumsQuery.refetch()} />
+          )}
+          {!albumsQuery.isLoading &&
+            !albumsQuery.isError &&
+            albums.length === 0 && (
+              <p style={{ color: 'var(--color-text-3)', fontSize: '0.875rem' }}>
+                {t('artist.noAlbums')}
+              </p>
+            )}
+          {albums.length > 0 && (
+            <div
+              style={{
+                display: 'grid',
+                gridTemplateColumns: 'repeat(auto-fill, minmax(9rem, 1fr))',
+                gap: '1rem',
+              }}
+            >
+              {albums.map((album) => (
+                <AlbumCard
+                  key={album.id}
+                  album={album}
+                  onClick={() => void navigate(`/albums/${album.id}`)}
+                />
+              ))}
+            </div>
+          )}
+        </section>
+
+        {/* All tracks */}
+        <section style={{ padding: '1.5rem 0 0.5rem' }}>
+          <h2
+            style={{
+              margin: '0 1.5rem 0.5rem',
+              fontSize: '1rem',
+              fontWeight: 600,
+            }}
+          >
+            {t('artist.tracks')}
+          </h2>
+          {tracksQuery.isLoading && <LoadingSkeleton rows={6} />}
+          {tracksQuery.isError && (
+            <ErrorState onRetry={() => tracksQuery.refetch()} />
+          )}
+          {!tracksQuery.isLoading &&
+            !tracksQuery.isError &&
+            tracks.length === 0 && (
+              <EmptyState
+                icon="♫"
+                title={t('artist.empty.title')}
+                description={t('artist.empty.description')}
+              />
+            )}
+          {tracks.map((track, i) => (
+            <TrackRow key={track.id} track={track} index={i} showAlbum />
+          ))}
+        </section>
+      </ScrollArea>
+    </div>
+  );
+}
+
+function AlbumCard({ album, onClick }: { album: Album; onClick: () => void }) {
+  const { t } = useTranslation();
+  const artUrl = getCoverUrl(album.artUrl);
+  return (
+    <Card
+      onClick={onClick}
+      style={{
+        cursor: 'pointer',
+        padding: '0.75rem',
+        display: 'flex',
+        flexDirection: 'column',
+        gap: '0.5rem',
+      }}
+    >
+      {artUrl ? (
+        <img
+          src={artUrl}
+          alt={album.title}
+          style={{
+            width: '100%',
+            aspectRatio: '1',
+            objectFit: 'cover',
+            borderRadius: 6,
+          }}
+        />
+      ) : (
+        <div style={{ width: '100%', aspectRatio: '1' }}>
+          <ArtTile seed={album.id} label={album.title} size={144} radius={6} />
+        </div>
+      )}
+      <div>
+        <div
+          style={{
+            fontWeight: 600,
+            fontSize: '0.8125rem',
+            overflow: 'hidden',
+            textOverflow: 'ellipsis',
+            whiteSpace: 'nowrap',
+          }}
+        >
+          {album.title}
+        </div>
+        <div style={{ fontSize: '0.6875rem', color: 'var(--color-text-3)' }}>
+          {album.year ? `${album.year} · ` : ''}
+          {t('library.albumCard.tracksDuration', {
+            count: album.trackCount,
+            duration: formatDuration(album.totalDurationMs),
+          })}
+        </div>
+      </div>
+    </Card>
+  );
 }

src/features/library/LibraryPage.tsx

@@ -216,7 +216,11 @@ export function LibraryPage() {
             {artistsQuery.data && (
               <div style={{ padding: '0.5rem 0' }}>
                 {artistsQuery.data.items.map((artist) => (
-                  <ArtistRow key={artist.id} artist={artist} />
+                  <ArtistRow
+                    key={artist.id}
+                    artist={artist}
+                    onClick={() => void navigate(`/artists/${artist.id}`)}
+                  />
                 ))}
               </div>
             )}
@@ -302,15 +306,23 @@ function AlbumCard({ album, onClick }: { album: Album; onClick: () => void }) {
   );
 }
 
-function ArtistRow({ artist }: { artist: Artist }) {
+function ArtistRow({
+  artist,
+  onClick,
+}: {
+  artist: Artist;
+  onClick: () => void;
+}) {
   const { t } = useTranslation();
   return (
     <div
+      onClick={onClick}
       style={{
         display: 'flex',
         alignItems: 'center',
         gap: '0.75rem',
         padding: '0.5rem 1.5rem',
+        cursor: 'pointer',
       }}
     >
       <div

src/i18n/locales/en.ts

@@ -108,6 +108,19 @@ const en = {
       description: 'This album has no tracks.',
     },
   },
+  artist: {
+    type: 'Artist',
+    play: '▶ Play all',
+    error: 'Failed to load artist',
+    meta: '{{albumCount}} albums · {{trackCount}} tracks',
+    albums: 'Albums',
+    tracks: 'Tracks',
+    noAlbums: 'No albums yet.',
+    empty: {
+      title: 'No tracks',
+      description: 'This artist has no tracks.',
+    },
+  },
   playlist: {
     type: 'Playlist',
     play: '▶ Play',

src/i18n/locales/ru.ts

@@ -110,6 +110,19 @@ const ru: Translations = {
       description: 'В этом альбоме нет треков.',
     },
   },
+  artist: {
+    type: 'Исполнитель',
+    play: '▶ Слушать всё',
+    error: 'Не удалось загрузить исполнителя',
+    meta: '{{albumCount}} альбомов · {{trackCount}} треков',
+    albums: 'Альбомы',
+    tracks: 'Треки',
+    noAlbums: 'Пока нет альбомов.',
+    empty: {
+      title: 'Нет треков',
+      description: 'У этого исполнителя нет треков.',
+    },
+  },
   playlist: {
     type: 'Плейлист',
     play: '▶ Слушать',