## What & why
Before this change the self-service confirmation and the openbaar register showed **different** identifiers, so a citizen could not look their registration back up (#78). Now both surface the same **reference**:
- **domain → ACL (write):** the domain `registrationId` is set as the zaak's `identificatie` on `POST /zaken`.
- **event-subscriber → ACL (read):** the subscriber reads the zaak's `identificatie` back through the ACL (§8.1 — only the ACL talks to ZGW) via a new `POST /zaken/reference`, and stores it on the projection row **and** the `processed_notifications` replay log.
- **BFF + openbaar:** the public view exposes `id/status/reference` (never bsn/naam) and searches by id or reference; the register's "Referentie" column shows the reference.
Storing the reference in the replay log keeps ADR-0008's **rebuild-is-log-only** invariant intact — `/admin/rebuild` reproduces the reference without re-reading the ACL.
Decision recorded in **ADR-0012**.
## Definition of Done
- [x] Linked issue: #78
- [x] Tests written first; red → green per layer
- [x] Unit + acceptance green (`make unit`): domain 49, acl 27, bff 20, event-subscriber 19, acceptance 7
- [x] Frontend lint + test green (`nx run-many -t lint test`)
- [x] Mutation ≥ break(90): acl 100%, event-subscriber 100%, bff 100%, domain 98.41% (pre-existing FlowableWorkflowClient baseline, untouched)
- [x] e2e extended: confirmation reference == register reference
- [x] openapi.json + api-client regenerated (drift guard green)
- [x] ADR-0012 added; demo-script note appended
- [x] `Acl__BaseUrl` wired for the subscriber in compose
closes#78
Reviewed-on: #79
Sharpen the projector tests so Stryker has no survivors (was 75%): assert a replayed
delivery never reaches the store (upsert count, not just row count), that two distinct
zaken get distinct rows (pins the idempotency key), that rebuild clears stale rows, and
a Theory over wrong kanaal/resource/actie combinations (pins the zaken/zaak/create guard).
Add the per-service Stryker config + solution; break threshold 90 (CLAUDE.md §5).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Failing unit + acceptance tests for the Event Subscriber's NotificationProjector:
a zaken/zaak/create notification yields one INGEDIEND projection row, duplicate
deliveries collapse to one row, non-zaak/non-create notifications are ignored, and
a rebuild repopulates the projection from the durable notification log (PRD §8.4).
The projector is a no-op stub so the tests compile and fail on the assertions; the
implementation follows in the green commit. The notification log doubles as the
idempotency guard and rebuild source so a rebuild needs no OpenZaak access (§8.1).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>