FEAT(trivy): add trivy operator

- for container vulnerability scanning
- Add Trivy Operator Helm chart (v0.31.0)
- Configure ServiceMonitor for Prometheus integration
- Enable vulnerability, config audit, and RBAC scanners
- Use Longhorn storage class for Trivy DB
- Exclude kube-system namespaces from scanning

trivy/kustomization.yaml

@@ -0,0 +1,3 @@
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+resources: []