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/(main)/dashboard/components/transcode-settings-dialog.tsx

@@ -43,6 +43,8 @@ export function TranscodeSettingsDialog({ open, onOpenChange }: Props) {
   const [confirmClear, setConfirmClear] = useState(false);
 
   useEffect(() => {
+    // Initialise controlled input from async data — intentional setState in effect
+    // eslint-disable-next-line react-hooks/set-state-in-effect
     if (settings) setTtl(settings.cleanup_ttl_hours);
   }, [settings]);