Merge dev into uat (PR #39) — QA-approved promotion

Resolves add/add conflict in audit-ci.jsonc: both branches independently
added the CTO-approved allowlist (PRI-854); identical content, kept the
POSIX-compliant trailing newline from uat/main. Also adds trailing newline
to dual-approval.yaml (missed in dev commit 990c796).

Changes promoted from dev:
- .github/workflows/dual-approval.yaml: Promotion Gate workflow (uat+main trigger)
- audit-ci.jsonc: CTO-approved allowlist for 3 inherited dev-only CVEs

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.github/workflows/dual-approval.yaml

@@ -0,0 +1,20 @@
+name: Promotion Gate
+
+# Calls the shared promotion gate workflow.
+# dev PRs: no gate (engineer self-merges).
+# uat PRs: QA approval required.
+# main PRs: UAT approval required (uat→main promotions).
+
+on:
+  pull_request_review:
+    types: [submitted, dismissed]
+  pull_request:
+    branches: [uat, main]
+    types: [opened, reopened, synchronize]
+
+jobs:
+  promotion-gate:
+    uses: privilegedescalation/.github/.github/workflows/dual-approval-check.yaml@main
+    secrets: inherit
+    with:
+      pr_number: ${{ github.event.pull_request.number }}