Implement complete recurring event drag modification system

- Add recurring edit modal with three modification options:
  • "Only this event" - Creates exception for single occurrence
  • "This and future events" - Splits series from occurrence forward
  • "All occurrences in this series" - Updates entire series time

- Enhance backend update API to support series modifications:
  • Add update_action parameter for recurring event operations
  • Implement time-only updates that preserve original start dates
  • Convert timestamped occurrence UIDs to base UIDs for series updates
  • Preserve recurrence rules during series modifications

- Fix recurring event drag operations:
  • Show modal for recurring events instead of direct updates
  • Handle EXDATE creation for single occurrence modifications
  • Support series splitting with UNTIL clause modifications
  • Maintain proper UID management for different modification types

- Clean up debug logging and restore page refresh for data consistency

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/components/calendar.rs

@@ -250,6 +250,7 @@ pub fn Calendar(props: &CalendarProps) -> Html {
                             on_event_context_menu={props.on_event_context_menu.clone()}
                             on_calendar_context_menu={props.on_calendar_context_menu.clone()}
                             on_create_event={Some(on_create_event)}
+                            on_create_event_request={props.on_create_event_request.clone()}
                             on_event_update={Some(on_event_update)}
                             context_menus_open={props.context_menus_open}
                             time_increment={*time_increment}