Migrate all Firestore triggers off the v1 API to firebase-functions/v2/firestore
(onDocumentCreated/Updated/Written); context.params→event.params, snap→event.data,
change.before/after→event.data.before/after. Region stays us-central1 (global option).
Hardening folded in (all reuse in-repo patterns):
- Adopt the shared sendPushToUser()/getUserTokens() helper in every trigger, removing
~7 copied token readers and the copied send/prune blocks. FCM tokens are no longer
logged in plaintext anywhere here (redacted inside push.ts).
- console.* → firebase-functions/logger (structured).
- Idempotency: new claimOnce() (atomic create-if-absent marker under
couples/{id}/notif_marks) dedupes at-least-once redelivery on the non-idempotent
senders (onAnswerWritten/Revealed, onMessageWritten, onCoupleLeave, onEntitlementChanged,
onDateReflectionWritten/Revealed, onDateHistoryCreated). Fail-open. onGameSessionUpdate/
onGamePartFinished/notifyOnDateMatch already had transactional claim-flags — preserved.
- onRestoreRequested: the plan's "claim" is implemented as the existing 60s time-WINDOW
(lastRestorePartnerAlertAt), not a permanent recipientUid marker — a permanent marker
would wrongly block legitimate re-requests (restore docs are deleted+recreated by design).
Faithful port of onGameSessionUpdate/onGamePartFinished (broad wildcard + allowlist kept);
the trigger split and read reorder are deferred to B6 as separate commits.
Build clean; 70 tests green (+ new idempotency.test.ts, push token/prune tests). Emulator
discovery loads all triggers as v2 in us-central1. firebase-functions still v5.1.1 (v6 bump
deferred to B6). dist rebuilt.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>