migrate all secrets from SOPS to Vault KV

- Add vault provider to root terragrunt.hcl (generated providers.tf)
- Delete stacks/vault/vault_provider.tf (now in generated providers.tf)
- Add 124 variable declarations + 43 vault_kv_secret_v2 resources to
  vault/main.tf to populate Vault KV at secret/<stack-name>
- Migrate 43 consuming stacks to read secrets from Vault KV via
  data "vault_kv_secret_v2" instead of SOPS var-file
- Add dependency "vault" to all migrated stacks' terragrunt.hcl
- Complex types (maps/lists) stored as JSON strings, decoded with
  jsondecode() in locals blocks

Bootstrap secrets (vault_root_token, vault_authentik_client_id,
vault_authentik_client_secret) remain in SOPS permanently.

Apply order: vault stack first (populates KV), then all others.

stacks/grampsweb/main.tf

@@ -2,8 +2,16 @@ variable "tls_secret_name" {
   type      = string
   sensitive = true
 }
-variable "mailserver_accounts" { type = map(any) }
 variable "nfs_server" { type = string }
+
+data "vault_kv_secret_v2" "secrets" {
+  mount = "secret"
+  name  = "grampsweb"
+}
+
+locals {
+  mailserver_accounts = jsondecode(data.vault_kv_secret_v2.secrets.data["mailserver_accounts"])
+}
 variable "redis_host" { type = string }
 variable "ollama_host" { type = string }
 variable "mail_host" { type = string }
@@ -81,7 +89,7 @@ locals {
     },
     {
       name  = "GRAMPSWEB_EMAIL_HOST_PASSWORD"
-      value = var.mailserver_accounts["info@viktorbarzin.me"]
+      value = local.mailserver_accounts["info@viktorbarzin.me"]
     },
     {
       name  = "GRAMPSWEB_EMAIL_USE_SSL"

stacks/grampsweb/providers.tf

@@ -1,7 +1,7 @@
 # Generated by Terragrunt. Sig: nIlQXj57tbuaRZEa
 variable "kube_config_path" {
-  type    = string
-  default = "~/.kube/config"
+  type      = string
+  default   = "~/.kube/config"
   sensitive = true
 }
 

stacks/grampsweb/terragrunt.hcl

@@ -6,3 +6,8 @@ dependency "platform" {
   config_path  = "../platform"
   skip_outputs = true
 }
+
+dependency "vault" {
+  config_path  = "../vault"
+  skip_outputs = true
+}