{"endpoint":"POST /api/webhook/airline","supported_event_types":["flight.disruption.created","passenger.disruption.assigned","accommodation.hotel.allocated","accommodation.transport.allocated"],"expected_header":"x-rh-signature: sha256=<hex of HMAC-SHA-256(secret, rawBody)>","idempotency":"By eventId. Repeat sends return 200 with status=duplicate.","note":"Modelled on Air India accommodations/v1/notifications contract."}