The publish chain works — the sink received it:
{"kanaal": "objecten", "resource": "object", "kenmerken": {"objectType": "…"},
"hoofdObject": "http://objecten.local:8000/api/v2/objects/a68d4c46-…", …}
The check just looked for the wrong thing. An NRC notification carries hoofdObject /
resourceUrl and kenmerken — never the record data — so the `reference` inside the
RegisterRecord it wrote was never going to appear in the delivered message. Grep the sink
for the object URL instead, which is what identifies the write.
Registers an abonnement on the `objecten` kanaal pointing at the existing
webhook sink, writes a RegisterRecord exactly as the ACL does on approval, and
waits for the delivery. That is the whole publish chain in one assertion:
Objecten → its celery worker → NRC → nrc-beat → the callback.
Fails today at the first hop, which is the point:
NRC POST /api/v1/abonnement → 400: {"name":"naam","code":"kanaal_naam",
"reason":"Kanaal met deze naam bestaat niet."}
Also splits S-19b (#150) into #152/#153 in BACKLOG.md — the notification wiring
and the projection re-source are independently deployable (CLAUDE.md §13).