replace count by for_each with declared set

terraform/projects/multiple-vm/variables.tf

@@ -7,4 +7,10 @@ variable "proxmox_api_token" {
   description = "Proxmox API token"
   type        = string
   sensitive   = true
+}
+
+variable "node_list" {
+  description = "List of node names in the Proxmox cluster"
+  type        = set(string)
+  default     = ["apex", "vertex", "zenith"]
 }