fix: restore tree dropped by 6d224861; land stem95su gdrive-sync (10m) [ci skip]

6d224861 came from a --no-checkout worktree whose empty index made the
commit drop every file except two. This restores 05b50d2b's full tree and
correctly adds stacks/stem95su/gdrive-sync.tf + the service-catalog stem95su
entry. Forward-only (parent=6d224861, no force-push); [ci skip] since the
live infra was never applied from the broken commit.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

stacks/authentik/main.tf

@@ -0,0 +1,25 @@
+# =============================================================================
+# Authentik Stack — Identity provider (SSO)
+# =============================================================================
+
+variable "tls_secret_name" { type = string }
+variable "redis_host" { type = string }
+
+data "vault_kv_secret_v2" "secrets" {
+  mount = "secret"
+  name  = "platform"
+}
+
+locals {
+  homepage_credentials = jsondecode(data.vault_kv_secret_v2.secrets.data["homepage_credentials"])
+}
+
+module "authentik" {
+  source            = "./modules/authentik"
+  tier              = local.tiers.cluster
+  tls_secret_name   = var.tls_secret_name
+  secret_key        = data.vault_kv_secret_v2.secrets.data["authentik_secret_key"]
+  postgres_password = data.vault_kv_secret_v2.secrets.data["authentik_postgres_password"]
+  redis_host        = var.redis_host
+  homepage_token    = try(local.homepage_credentials["authentik"]["token"], "")
+}