feat(genius): fetch artist avatars by name and match names with transliteration suffix

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

services/api/internal/genius/metadata_test.go

@@ -95,3 +95,25 @@ func TestAnnotations(t *testing.T) {
 	require.True(t, notes[0].Verified)
 	require.Equal(t, "https://genius.com/annotations/1", notes[0].Url)
 }
+
+type fakeArtists struct {
+	songs  []Song
+	artist Artist
+}
+
+func (f fakeArtists) Search(context.Context, string) ([]Song, error) { return f.songs, nil }
+func (f fakeArtists) Artist(context.Context, int64) (Artist, error)  { return f.artist, nil }
+
+func TestArtistImage(t *testing.T) {
+	ctx := context.Background()
+	src := fakeArtists{songs: []Song{
+		{Artist: Artist{ID: 1, Name: "Other", ImageURL: "https://images.genius.com/other.jpg"}},
+		{Artist: Artist{ID: 2, Name: "Некич (Nekich)"}},
+	}, artist: Artist{ID: 2, ImageURL: "https://images.genius.com/nekich.jpg"}}
+	img, err := artistImage(ctx, src, "некич")
+	require.NoError(t, err)
+	require.Equal(t, "https://images.genius.com/nekich.jpg", img)
+	img, err = artistImage(ctx, src, "Unknown")
+	require.NoError(t, err)
+	require.Empty(t, img)
+}