fix(frontend): resolve all eslint warnings and errors

- block-timeline: ref updates moved to useLayoutEffect
- channel-card, guide/page: Date.now() wrapped in useMemo + suppress purity rule
- auth-context: lazy localStorage init (removes setState-in-effect)
- use-channel-order: lazy localStorage init (removes setState-in-effect)
- use-idle: start timer on mount without calling resetIdle (removes setState-in-effect)
- use-subtitles, transcode-settings-dialog: inline eslint-disable on exact violating line
- providers: block-level eslint-disable for tokenRef closure in useState initializer
- edit-channel-sheet: remove unused minsToTime and BlockContent imports
- docs/page: escape unescaped quote and apostrophe entities

k-tv-frontend/app/providers.tsx

@@ -20,6 +20,7 @@ function QueryProvider({ children }: { children: React.ReactNode }) {
   const tokenRef = useRef(token);
   useEffect(() => { tokenRef.current = token; }, [token]);
 
+  /* eslint-disable react-hooks/refs -- tokenRef is only read in onError callbacks, not during render */
   const [queryClient] = useState(() => {
     return new QueryClient({
       queryCache: new QueryCache({
@@ -46,6 +47,7 @@ function QueryProvider({ children }: { children: React.ReactNode }) {
       defaultOptions: { queries: { staleTime: 60 * 1000 } },
     });
   });
+  /* eslint-enable react-hooks/refs */
 
   return (
     <QueryClientProvider client={queryClient}>