T-0.5 Kyverno L0 policies + CLI tests + admission scaffolding (R-TEST-01, R-NET-01, R-SEC-01/02, R-IDP-02, R-GITOPS-02)

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

platform/kyverno/admission/namespace.yaml

@@ -0,0 +1,9 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: kyverno
+  labels:
+    # Platform namespace -- deliberately NOT an application namespace, so the
+    # app-scoped policies do not apply to Kyverno's own workloads.
+    homelab.keithjackson.dev/app-namespace: "false"
+    pod-security.kubernetes.io/enforce: restricted