ev/book-series! / ev/cancel-series! apply a booking/cancel to every occurrence
of one event in a window (RSVP the whole weekly class), returning per-
occurrence (occ-key status) results; capacity still enforced per occurrence
(some :booked, some :full), idempotent re-book (:already). ev/series-count,
ev/series-booked. 341/341 green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
ev/book-checked! prevents an attendee double-booking themselves across
different events: consults their persist-derived availability (ev/free-p?) for
the occurrence window, returns :time-conflict on overlap else the normal
ev/book-occ! result. Re-booking the same occurrence stays idempotent
(:already); other actors unaffected. ev/would-time-conflict? predicate.
311/311 green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
