feat(artist): sort albums by year on artist detail (#877)

* feat(artist): year sort for albums section on artist detail

Add a sort dropdown next to "Albums by …" with release-type grouping (default),
newest-first, and oldest-first by album year.

* chore: note PR #877 in CHANGELOG and settings credits

* fix(artist): toggle year sort inside release groups, session per server

Replace dropdown with a click-to-toggle newest/oldest button. Keep release-type
blocks; sort albums by year within each group. Persist order in session store.

src/store/artistAlbumYearSortStore.test.ts

@@ -0,0 +1,32 @@
+import { describe, expect, it, beforeEach } from 'vitest';
+import {
+  DEFAULT_ARTIST_ALBUM_YEAR_ORDER,
+  useArtistAlbumYearSortStore,
+} from './artistAlbumYearSortStore';
+
+describe('artistAlbumYearSortStore', () => {
+  beforeEach(() => {
+    useArtistAlbumYearSortStore.setState({ orderByServer: {} });
+  });
+
+  it('defaults to newest first per server', () => {
+    expect(useArtistAlbumYearSortStore.getState().yearOrderFor('s1')).toBe(
+      DEFAULT_ARTIST_ALBUM_YEAR_ORDER,
+    );
+  });
+
+  it('toggles between newest and oldest for the same server', () => {
+    const { toggleYearOrder, yearOrderFor } = useArtistAlbumYearSortStore.getState();
+    toggleYearOrder('s1');
+    expect(yearOrderFor('s1')).toBe('yearAsc');
+    toggleYearOrder('s1');
+    expect(yearOrderFor('s1')).toBe('yearDesc');
+  });
+
+  it('keeps order per server independently', () => {
+    const { toggleYearOrder, yearOrderFor } = useArtistAlbumYearSortStore.getState();
+    toggleYearOrder('s1');
+    expect(yearOrderFor('s1')).toBe('yearAsc');
+    expect(yearOrderFor('s2')).toBe('yearDesc');
+  });
+});

src/store/artistAlbumYearSortStore.ts

@@ -0,0 +1,27 @@
+import { create } from 'zustand';
+
+import type { ArtistAlbumYearOrder } from '../utils/library/sortArtistAlbums';
+
+export const DEFAULT_ARTIST_ALBUM_YEAR_ORDER: ArtistAlbumYearOrder = 'yearDesc';
+
+interface ArtistAlbumYearSortStore {
+  orderByServer: Record<string, ArtistAlbumYearOrder>;
+  yearOrderFor: (serverId: string) => ArtistAlbumYearOrder;
+  toggleYearOrder: (serverId: string) => void;
+}
+
+export const useArtistAlbumYearSortStore = create<ArtistAlbumYearSortStore>((set, get) => ({
+  orderByServer: {},
+
+  yearOrderFor: (serverId) =>
+    get().orderByServer[serverId] ?? DEFAULT_ARTIST_ALBUM_YEAR_ORDER,
+
+  toggleYearOrder: (serverId) => {
+    if (!serverId) return;
+    const current = get().yearOrderFor(serverId);
+    const next: ArtistAlbumYearOrder = current === 'yearDesc' ? 'yearAsc' : 'yearDesc';
+    set(s => ({
+      orderByServer: { ...s.orderByServer, [serverId]: next },
+    }));
+  },
+}));