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

modules/vault_cluster/modules/vault_policy/variables.tf

@@ -0,0 +1,12 @@
+variable "policy_name" {
+  description = "Name of the Vault policy"
+  type        = string
+}
+
+variable "policy_rules" {
+  description = "List of policy rules for this policy"
+  type = list(object({
+    path         = string
+    capabilities = list(string)
+  }))
+}