feat(library): add media library browsing functionality

- Introduced new `library` module in the API routes to handle media library requests.
- Enhanced `AppState` to include a media provider for library interactions.
- Defined new `IMediaProvider` trait methods for listing collections, series, and genres.
- Implemented Jellyfin media provider methods for fetching collections and series.
- Added frontend components for selecting series and displaying filter previews.
- Created hooks for fetching collections, series, and genres from the library.
- Updated media filter to support series name and search term.
- Enhanced API client to handle new library-related endpoints.

k-tv-frontend/hooks/use-library.ts

@@ -0,0 +1,62 @@
+"use client";
+
+import { useQuery } from "@tanstack/react-query";
+import { api } from "@/lib/api";
+import { useAuthContext } from "@/context/auth-context";
+import type { MediaFilter } from "@/lib/types";
+
+const STALE = 10 * 60 * 1000; // 10 min — library metadata rarely changes in a session
+
+/** List top-level collections (Jellyfin libraries, Plex sections, etc.) */
+export function useCollections() {
+  const { token } = useAuthContext();
+  return useQuery({
+    queryKey: ["library", "collections"],
+    queryFn: () => api.library.collections(token!),
+    enabled: !!token,
+    staleTime: STALE,
+  });
+}
+
+/**
+ * List TV series, optionally scoped to a collection.
+ * All series are loaded upfront so the series picker can filter client-side
+ * without a request per keystroke.
+ */
+export function useSeries(collectionId?: string) {
+  const { token } = useAuthContext();
+  return useQuery({
+    queryKey: ["library", "series", collectionId ?? null],
+    queryFn: () => api.library.series(token!, collectionId),
+    enabled: !!token,
+    staleTime: STALE,
+  });
+}
+
+/** List available genres, optionally scoped to a content type. */
+export function useGenres(contentType?: string) {
+  const { token } = useAuthContext();
+  return useQuery({
+    queryKey: ["library", "genres", contentType ?? null],
+    queryFn: () => api.library.genres(token!, contentType),
+    enabled: !!token,
+    staleTime: STALE,
+  });
+}
+
+/**
+ * Fetch items matching a filter for the block editor's "Preview results" panel.
+ * Pass `enabled: false` until the user explicitly requests a preview.
+ */
+export function useLibraryItems(
+  filter: Pick<MediaFilter, "content_type" | "series_name" | "collections" | "search_term" | "genres"> | null,
+  enabled: boolean,
+) {
+  const { token } = useAuthContext();
+  return useQuery({
+    queryKey: ["library", "items", filter],
+    queryFn: () => api.library.items(token!, filter!, 30),
+    enabled: !!token && enabled && !!filter,
+    staleTime: 2 * 60 * 1000,
+  });
+}