A Download all attendees CSV button on the Bookings admin Summary tab, alongside the existing summary export. It flattens every booking's attendees across all events into one report, with columns Event, Date, Time, Group, Attendee, Email, Phone, Status and Booked.
Previously a coordinator could only see attendee emails one event at a time via the Per-Event Detail tab, needing a separate CSV per event. This produces every booker email in a single report.
Client-only change reusing the existing CSV export component. The data is already loaded in allBookings, so no server change is required.