feat: enhance calendar with view sync, Redux fixes, and dynamic slot label dimming

- Sync calendar view state between Calendar and Menubar components
- Fix Redux serialization errors by using string dates instead of Date objects
- Add null checks for eventResize handler to prevent undefined errors
- Implement dynamic slot label dimming near current time indicator
- Slot labels fade to opacity 0.2 when now indicator is within 15 minutes
- Add smooth CSS transitions for better user experience
- Handle edge cases around midnight for proper time calculation
- Update slot label visibility on view changes and time updates

src/components/Event/EventDuplicate.tsx

@@ -15,9 +15,9 @@ export default function EventDuplication({
   const [openModal, setOpenModal] = useState(false);
   const [selectedRange, setSelectedRange] = useState<DateSelectArg | null>({
     start: new Date(event.start),
-    startStr: new Date(event.start).toISOString(),
+    startStr: event.start,
     end: new Date(event.end ?? ""),
-    endStr: new Date(event.end ?? "").toISOString(),
+    endStr: event.end ?? "",
     allDay: event.allday ?? false,
   } as DateSelectArg);
   const calendarRef = useRef<CalendarApi | null>(null);