Restore case-insensitive credential scan

[sehkone]

Restore case-insensitive credential scan

Context

The registrar-redteam scenario proves that the manifest-defined registrar client bundle contains no copied OpenBao or AppRole credentials. Its credential-scan expression previously matched conventional credential labels case-insensitively. The current command at scripts/impl/lib/registrar-docker.sh no longer uses grep -i, so casing variants of the conventional token and AppRole labels can evade the label branch unless an independent bare-value pattern happens to match.

Scope

• Restore case-insensitive matching for the conventional credential-label alternatives in registrar_docker_assert_no_backend_credentials.
• Preserve the direct bare-value alternatives, the recursive scan's staged-bundle boundary, and the manifest regular-file-set assertion.
• Extend the focused non-Docker bundle-scan test to prove that casing variants of X-Vault-Token, X-OpenBao-Token, OPENBAO_TOKEN, VAULT_TOKEN, role_id, and secret_id are rejected when paired with values that do not independently match a bare-value alternative.
• Keep the existing exact-cased and bare-value regression cases.

Acceptance criteria

• The staged-bundle scan rejects conventional OpenBao-token and AppRole labels regardless of casing.
• Each new labelled-form regression input is rejected because of its label, not because its value matches a separate bare token or UUID pattern.
• The focused fixture still accepts the credential-free registrar certificate, key, endpoint configuration, pin, and CA inputs.
• The scan remains recursive only within the read-only manifest-staged bundle, and the manifest regular-file-set assertion remains intact.
• The live registrar-redteam scenario continues to pass.

Constraints

• Scan only the manifest-defined registrar-leak bundle; do not scan the container, daemon-private material, or unrelated host files.
• Do not add production test hooks, inspection APIs, or fault-injection seams.
• Do not change registrar endpoint authorization, the Python client architecture, or the unknown-operation assertion.
• Do not decide or broaden the supported bare OpenBao token-prefix set; that question is outside this issue.

Out of scope

• Recognizing additional bare OpenBao token families.
• Changes to the registrar endpoint protocol, certificate pinning, socket checks, or audit/capacity assertions.

Test plan

• Run the focused bundle-scan coverage through registrar_redteam_boundary_assertions_are_conclusive_without_docker.
• Run scripts/preflight/ci/e2e-matrix.sh where the environment supports the registrar-redteam Docker scenario; otherwise record the root prerequisite that prevents the local run and rely on its CI gate.
• Run cargo fmt -- --check --config group_imports=StdExternalCrate and cargo clippy --all-targets -- -D warnings.

Dependencies

Part of #972. No implementation prerequisite.

Pointers

• scripts/impl/lib/registrar-docker.sh — registrar_docker_assert_no_backend_credentials
• tests/e2e/registrar/registrar_redteam_assertions_test.sh — focused staged-bundle scan coverage
• tests/registrar_redteam_assertions.rs — non-Docker test entry point

[sehkone]

Verification summary

• Delivery: COMPLETE — the merged code delivers what the issue asked for. (the auditor's own verdict)
• Extra changes: NO_EXTRA_CHANGES — the merged code changed nothing beyond what the issue asked for. (the auditor's own verdict)
• Defects: NO_DEFECT — the merged pull requests left no defect of their own behind. (the auditor's own verdict)

Delivery decides whether this issue is closed or reopened. Defects widens what the follow-up filing considers. Extra changes gates nothing — it is an observation for a human; the report names what went beyond the issue.

Implementing pull requests, at the merge commits this audit read:

• Restore case-insensitive credential scan (#975) #976 — c2c31f29a46ca2623240b5a754eb6ef8bba3d5a3 (the tree the audit read)

The full report — the assessment included verbatim — stays local, at:
~/.agentcoop/runs/aicers/bootroot/verify/OTc1/report.md

Findings this run did not file:

Finding not filed — This is an improvement nobody requested.
Summary (the filing turn's statement):
The added uppercase HVS. acceptance assertion records existing behavior, but the issue did not require that guard.
Observed (the filing turn's statement):
tests/e2e/registrar/registrar_redteam_assertions_test.sh:94