extract remaining 19 modules from platform, complete stack split [ci skip]

Phase 3: all 27 platform modules now run as independent stacks.
Platform reduced to empty shell (outputs only) for backward compat
with 72 app stacks that declare dependency "platform".
Fixed technitium cross-module dashboard reference by copying file.
Woodpecker pipeline applies all 27+1 stacks in parallel via loop.
All applied with zero destroys.

stacks/iscsi-csi/main.tf

@@ -0,0 +1,14 @@
+variable "nfs_server" { type = string }
+
+data "vault_kv_secret_v2" "secrets" {
+  mount = "secret"
+  name  = "platform"
+}
+
+module "iscsi-csi" {
+  source                  = "./modules/iscsi-csi"
+  tier                    = local.tiers.cluster
+  truenas_host            = var.nfs_server
+  truenas_api_key         = data.vault_kv_secret_v2.secrets.data["truenas_api_key"]
+  truenas_ssh_private_key = data.vault_kv_secret_v2.secrets.data["truenas_ssh_private_key"]
+}