- Create Phase 4 ArgoCD Application (terraform-apply) - PostSync Hook Job runs: terraform init && terraform apply -auto-approve - ServiceAccount + ClusterRole for cluster-admin RBAC - S3 credentials encrypted with SOPS (terraform-s3-secrets.enc.yaml) - Pre-commit hook blocks local 'terraform apply' — all changes via git push - True IaC: modify terraform/*.tf → git push → ArgoCD applies automatically