Add agent security skills for Codex and Claude Code

Same skills in .agents/skills (Codex) and .claude/skills (Claude Code):
codeguard, security-review, dependency-vetting, pre-release-gate,
authz-idor-audit, threat-model-light. Source: cj/claude-skills.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.claude/skills/codeguard/rules/codeguard-0-cloud-orchestration-kubernetes.md

@@ -0,0 +1,35 @@
+---
+description: Kubernetes hardening (RBAC, admission policies, network policies, secrets, supply chain)
+languages:
+- yaml
+alwaysApply: false
+tags:
+- infrastructure
+---
+
+rule_id: codeguard-0-cloud-orchestration-kubernetes
+
+## Cloud & Orchestration (Kubernetes)
+
+Kubernetes cluster and workload hardening: identity, policy, networking, secrets, and supply chain controls.
+
+### Controls
+- Identity & RBAC: least privilege for users and service accounts; separate namespaces; bind only needed roles.
+- Policy: admission controls (OPA/Gatekeeper/Kyverno) for image sources, capabilities, root, network policies, and required labels/annotations.
+- Networking: default‑deny with network policies; explicit egress allow‑lists; service identity/mTLS within mesh where applicable.
+- Secrets: use KMS providers; avoid plaintext in manifests; rotate regularly; restrict secret mount paths.
+- Nodes: hardened OS, auto‑updates, minimal attack surface; isolate sensitive workloads with taints/tolerations and dedicated nodes.
+- Supply chain: verify image signatures; enforce provenance (SLSA/Sigstore) in admission.
+
+### Checklist
+- Namespaces per team/app; RBAC roles scoped; audit logging enabled.
+- Admission policies enforce image provenance, non‑root, dropped capabilities, read‑only root FS, and network policy presence.
+- Network policies in place for ingress/egress; service accounts scoped per deployment.
+
+### Verification
+- Cluster conformance and CIS benchmark scans.
+- Policy tests in CI for manifests (OPA unit tests); periodic admission dry‑run.
+
+### Incident Readiness
+- Enable audit logs and centralize; restrict access to etcd; backup/restore tested.
+- Define break‑glass roles with MFA and time‑bound approvals.