[Bug] Frontend RecurringEvent CRUD does not trigger backend event expansion or check-in processing

### Overview

When a user creates or updates a recurring event through the Manage Projects UI, the backend workers that generate `Event` documents and set `checkInReady` are never called — only a 30-minute cron fires them. If the cron window has already passed for the current day, the meeting never appears on the Check In screen.

### Action Items

- Investigate why creating or updating a recurring event in the Manage Projects UI does not immediately reflect on the Check In screen — trace the connection between the frontend CRUD calls and the backend workers responsible for generating events and setting check-in availability.
- Ensure that when a recurring event is created or updated, the backend processes it in a timely way rather than waiting for the next scheduled cron window.
- Investigate why the manual "set check-in ready" toggle on the admin dashboard and project leader dashboard appears to have no effect.
- Review date/time handling in the check-in availability logic for potential comparison issues.

### Resources/Instructions

- Related bug report: #2172 (Check In Screen Showing No Meetings Available)
- Affected workers: `backend/workers/createRecurringEvents.js`, `backend/workers/openCheckins.js`, `backend/workers/closeCheckins.js`
- Affected controller: `backend/controllers/recurringEvent.controller.js`