zhi
e561298c97
BE-CAL-API-003: implement Calendar edit API for real and virtual slots
- Add TimeSlotEdit schema (partial update, all fields optional)
- Add TimeSlotEditResponse schema
- Add PATCH /calendar/slots/{slot_id} for editing real slots
- Add PATCH /calendar/slots/virtual/{virtual_id} for editing virtual slots
- Triggers materialization before applying edits
- Detaches from plan after edit
- Both endpoints enforce:
- Past-slot immutability guard
- Overlap detection (excluding self)
- Plan detachment on edit
- Workload warnings in response