GPT-4.1 cross-family review of the policy surface (no BLOCK): FIX applied
to the cross-account shoc-backend-dev Decrypt statement and both Lambda
role KMS grants (the key is only ever used via Secrets Manager); its
invariant-enforcement QUESTION answered durably with
tests/test_cross_account_principal_pin.py (any new foreign IAM principal
in cdk/ fails CI). Scanner mediums fixed: delivery.py and the replay
script now refuse non-https URLs (urllib follows file:// and http://).
SQS metadata-action and dynamodb:ListStreams NITs skipped: standard CDK
grant shapes; ListStreams has no resource-level scoping. The 4 gitleaks
HIGHs on docs/shoc-webhook-test-vectors.json are deliberate non-secrets
(shared receiver-verification vectors) suppressed machine-level with
justification.