tofu config and docs

.tofu/platforms/upc/modules/cluster/variables.tf

@@ -38,6 +38,12 @@ variable "control_plane_ip_filter" {
   default     = ["0.0.0.0/0"]
 }
 
+variable "storage_size" {
+  description = "Storage size in GB for worker nodes (overrides plan default via cloud_native_plan block)"
+  type        = number
+  default     = null
+}
+
 variable "tags" {
   description = "Labels to apply to resources"
   type        = map(string)