feat(sync): auto-refresh on Jellyfin LibraryChanged events

Handle the server's LibraryChanged WebSocket message to invalidate
library-dependent React Query caches when items are added/updated/
removed, so newly added episodes/movies appear without a manual
refresh. Debounced to coalesce a scan's burst of events.

Add useRefreshLibraryOnFocus as a fallback that re-checks on screen
focus (throttled, online-only, skips first focus), wired into home
(mobile + TV) and the library pages.

app/(auth)/(tabs)/(libraries)/[libraryId].tsx

@@ -40,6 +40,7 @@ import { useScaledTVPosterSizes } from "@/constants/TVPosterSizes";
 import { useScaledTVTypography } from "@/constants/TVTypography";
 import useRouter from "@/hooks/useAppRouter";
 import { useOrientation } from "@/hooks/useOrientation";
+import { useRefreshLibraryOnFocus } from "@/hooks/useRefreshLibraryOnFocus";
 import { useTVItemActionModal } from "@/hooks/useTVItemActionModal";
 import { useTVOptionModal } from "@/hooks/useTVOptionModal";
 import * as ScreenOrientation from "@/packages/expo-screen-orientation";
@@ -104,6 +105,10 @@ const Page = () => {
 
   const { orientation } = useOrientation();
 
+  // Fallback refresh for newly added content when returning to the library
+  // (primary path is the LibraryChanged WebSocket event).
+  useRefreshLibraryOnFocus();
+
   const { t } = useTranslation();
   const router = useRouter();
   const { showOptions } = useTVOptionModal();