feat(web): add search query helpers (summary + 3 facet infinite queries)

createSearchQuery hits /api/search with limit=10 (the main /search
page summary). createSearchArtistsInfiniteQuery /
createSearchAlbumsInfiniteQuery / createSearchTracksInfiniteQuery each
hit /api/search with limit=50 and project to their own facet, used by
the per-facet overflow pages. All four are gated by q.length > 0 so
empty queries don't fire.

web/src/lib/api/queries.test.ts

@@ -15,3 +15,18 @@ describe('qk key generators', () => {
     expect(qk.album('xyz')).toEqual(['album', 'xyz']);
   });
 });
+
+describe('qk search keys', () => {
+  test('search summary key includes q', () => {
+    expect(qk.search('foo')).toEqual(['search', { q: 'foo' }]);
+  });
+  test('searchArtists key includes q', () => {
+    expect(qk.searchArtists('foo')).toEqual(['searchArtists', { q: 'foo' }]);
+  });
+  test('searchAlbums key includes q', () => {
+    expect(qk.searchAlbums('foo')).toEqual(['searchAlbums', { q: 'foo' }]);
+  });
+  test('searchTracks key includes q', () => {
+    expect(qk.searchTracks('foo')).toEqual(['searchTracks', { q: 'foo' }]);
+  });
+});

web/src/lib/api/queries.ts

@@ -1,14 +1,20 @@
 import { createQuery, createInfiniteQuery } from '@tanstack/svelte-query';
 import { api } from './client';
-import type { ArtistRef, ArtistDetail, AlbumDetail, Page } from './types';
+import type { ArtistRef, ArtistDetail, AlbumDetail, Page, SearchResponse } from './types';
 
 export type ArtistSort = 'alpha' | 'newest';
 export const ARTIST_PAGE_SIZE = 50;
+export const SEARCH_SUMMARY_LIMIT = 10;
+export const SEARCH_FACET_PAGE_SIZE = 50;
 
 export const qk = {
   artists: (sort: ArtistSort) => ['artists', { sort }] as const,
   artist:  (id: string)       => ['artist', id] as const,
   album:   (id: string)       => ['album', id] as const,
+  search:        (q: string) => ['search', { q }] as const,
+  searchArtists: (q: string) => ['searchArtists', { q }] as const,
+  searchAlbums:  (q: string) => ['searchAlbums',  { q }] as const,
+  searchTracks:  (q: string) => ['searchTracks',  { q }] as const,
 };
 
 export function createArtistsQuery(sort: ArtistSort) {
@@ -39,3 +45,62 @@ export function createAlbumQuery(id: string) {
     queryFn: () => api.get<AlbumDetail>(`/api/albums/${id}`),
   });
 }
+
+export function createSearchQuery(q: string) {
+  return createQuery({
+    queryKey: qk.search(q),
+    queryFn: () =>
+      api.get<SearchResponse>(
+        `/api/search?q=${encodeURIComponent(q)}&limit=${SEARCH_SUMMARY_LIMIT}`
+      ),
+    enabled: q.length > 0
+  });
+}
+
+export function createSearchArtistsInfiniteQuery(q: string) {
+  return createInfiniteQuery({
+    queryKey: qk.searchArtists(q),
+    queryFn: ({ pageParam = 0 }) =>
+      api.get<SearchResponse>(
+        `/api/search?q=${encodeURIComponent(q)}&limit=${SEARCH_FACET_PAGE_SIZE}&offset=${pageParam}`
+      ).then((r) => r.artists),
+    initialPageParam: 0,
+    getNextPageParam: (last) => {
+      const loaded = last.offset + last.items.length;
+      return loaded >= last.total ? undefined : loaded;
+    },
+    enabled: q.length > 0
+  });
+}
+
+export function createSearchAlbumsInfiniteQuery(q: string) {
+  return createInfiniteQuery({
+    queryKey: qk.searchAlbums(q),
+    queryFn: ({ pageParam = 0 }) =>
+      api.get<SearchResponse>(
+        `/api/search?q=${encodeURIComponent(q)}&limit=${SEARCH_FACET_PAGE_SIZE}&offset=${pageParam}`
+      ).then((r) => r.albums),
+    initialPageParam: 0,
+    getNextPageParam: (last) => {
+      const loaded = last.offset + last.items.length;
+      return loaded >= last.total ? undefined : loaded;
+    },
+    enabled: q.length > 0
+  });
+}
+
+export function createSearchTracksInfiniteQuery(q: string) {
+  return createInfiniteQuery({
+    queryKey: qk.searchTracks(q),
+    queryFn: ({ pageParam = 0 }) =>
+      api.get<SearchResponse>(
+        `/api/search?q=${encodeURIComponent(q)}&limit=${SEARCH_FACET_PAGE_SIZE}&offset=${pageParam}`
+      ).then((r) => r.tracks),
+    initialPageParam: 0,
+    getNextPageParam: (last) => {
+      const loaded = last.offset + last.items.length;
+      return loaded >= last.total ? undefined : loaded;
+    },
+    enabled: q.length > 0
+  });
+}