Two write-path cache bugs surfaced during Gate 2 live testing:
P1 (delete didn't work / ghost event): syncCalendar only UPSERTED events
present on Fastmail and never removed cache rows for events that disappeared.
A successful CalDAV delete left the row in calendar_events forever, so
GET /api/events kept returning it and the UI showed a ghost that 'wouldn't
delete' (even after refresh). Add a prune step: delete calendar_events rows for
this calendar whose uid is absent from the server response (scoped to cal.id so
it never touches another calendar or the other member's rows — BUG B). Empty
server result prunes the whole calendar's cache.
P2 (edit needed a manual refresh): the outbox worker marked a row 'done' BEFORE
triggerTargetedResync refreshed the cache. The PWA's SyncStateToast invalidates
['events'] the instant sync-status flips to 'done', so it refetched stale cache.
Re-sync first, then mark done — 'done' now guarantees the cache reflects the write.
Tests: +2 prune regressions (present-subset prune, empty-server prune-all).
Lucas Berger
98753d8e34