messaging-adapter-parity

# Messaging Adapter Parity ## Goal Prevent adapter-specific regressions by validating behavior contracts across messaging backends. ## Contract Areas - User-visible reply behavior - Status update behavior (`surfaced` vs `not surfaced`) - Delivery receipt ack/failure semantics - Retry behavior and bounded backoff - Error mapping and logging clarity ## Parity Checklist - For every changed adapter path, compare expected behavior with at least one other adapter. - If an adapter intentionally does not surface a status, ensure receipt handling still converges correctly. - Ensure unsupported features degrade gracefully and predictably. - Ensure worker terminal notices cannot loop indefinitely. ## Verification Checklist - Run targeted tests for the touched adapter. - Run targeted tests for receipt ack/failure paths. - Run at least one parity comparison check across adapters. - Run broad gate checks after targeted checks pass. ## Required Handoff - Adapter paths changed - Contract decisions made - Receipt behavior outcomes - Verification evidence - Residual parity gaps