feat(kyverno): add policy engine with security baseline

- Kyverno 3.3.4 via Helm (HA config: 3 admission, 2 background replicas)
- Validation policies:
  - disallow-privileged-containers (Enforce)
  - require-resource-limits (Enforce)
  - require-labels (Audit - standard k8s labels)
  - require-run-as-non-root (Audit)
  - disallow-latest-tag (Enforce - GitOps reproducibility)
- Mutating policy:
  - add-default-securitycontext (seccomp, drop caps, read-only fs)
- System namespaces excluded (kube-system, kyverno, istio-system)
- Auto-discovered by ArgoCD ApplicationSet

Reference: CIS Kubernetes Benchmark, Pod Security Standards

infrastructure/kyverno/policies/require-labels.yaml

@@ -0,0 +1,69 @@
+# infrastructure/kyverno/policies/require-labels.yaml
+# Enforces standard labeling for all workloads
+# Enables proper resource organization and cost tracking
+apiVersion: kyverno.io/v1
+kind: ClusterPolicy
+metadata:
+  name: require-labels
+  annotations:
+    policies.kyverno.io/title: Require Labels
+    policies.kyverno.io/category: Best Practices
+    policies.kyverno.io/severity: medium
+    policies.kyverno.io/subject: Pod, Deployment, StatefulSet, DaemonSet
+    policies.kyverno.io/description: >-
+      Labels are essential for organizing, filtering, and managing
+      Kubernetes resources. This policy requires standard labels on
+      all workloads.
+spec:
+  validationFailureAction: Audit  # Start in audit mode
+  background: true
+  rules:
+    - name: check-deployment-labels
+      match:
+        any:
+          - resources:
+              kinds:
+                - Deployment
+                - StatefulSet
+                - DaemonSet
+      exclude:
+        any:
+          - resources:
+              namespaces:
+                - kube-system
+                - kyverno
+      validate:
+        message: "Workloads must have 'app.kubernetes.io/name' and 'app.kubernetes.io/part-of' labels."
+        pattern:
+          metadata:
+            labels:
+              app.kubernetes.io/name: "?*"
+              app.kubernetes.io/part-of: "?*"
+    - name: check-pod-labels
+      match:
+        any:
+          - resources:
+              kinds:
+                - Pod
+      exclude:
+        any:
+          - resources:
+              namespaces:
+                - kube-system
+                - kyverno
+              # Exclude pods created by controllers (they inherit parent labels)
+              selector:
+                matchLabels:
+                  app.kubernetes.io/managed-by: "*"
+      preconditions:
+        all:
+          # Only check standalone pods (not owned by ReplicaSet, etc.)
+          - key: "{{ request.object.metadata.ownerReferences[] || `[]` | length(@) }}"
+            operator: Equals
+            value: 0
+      validate:
+        message: "Pods must have 'app.kubernetes.io/name' label."
+        pattern:
+          metadata:
+            labels:
+              app.kubernetes.io/name: "?*"