feat: major restructuring in migration to terragrunt

- migrate from individual terraform files to config-driven terragrunt module structure
- add vault_cluster module with config discovery system
- replace individual .tf files with centralized config.hcl
- restructure auth and secret backends as configurable modules
- move auth roles and secret backends to yaml-based configuration
- convert policies from .hcl to .yaml format, add rules/auth definition
- add pre-commit hooks for yaml formatting and file cleanup
- add terragrunt cache to gitignore
- update makefile with terragrunt commands and format target

resources/secret_backend/kubernetes/au/syd1/roles/cluster-admin.yaml

@@ -0,0 +1,26 @@
+---
+rules:
+  - apiGroups:
+      - ""
+      - "postgresql.cnpg.io"
+      - "cert-manager.io"
+      - "rbac.authorization.k8s.io"
+      - "batch"
+      - "secrets.hashicorp.com"
+      - "storage.k8s.io"
+      - "apps"
+      - "apiextensions.k8s.io"
+      - "externaldns.k8s.io"
+      - "autoscaling"
+      - "networking.k8s.io"
+      - "purelb.io"
+      - "nfd.k8s-sigs.io"
+      - "policy"
+      - "metrics.k8s.io"
+      - "logstash.k8s.elastic.co"
+      - "elasticsearch.k8s.elastic.co"
+      - "kibana.k8s.elastic.co"
+    resources:
+      - "*"
+    verbs:
+      - "*"