feat: refactor infra to cp/wk kubeadm topology

Provision 3 thin control planes and 3 workers with role-specific sizing and VMID ranges (701/711), generate per-node cloud-init snippets with SSH key injection, and add NixOS kubeadm host/module scaffolding for cp-1..3 and wk-1..3.

terraform/variables.tf

@@ -27,20 +27,74 @@ variable "clone_template" {
   type = string
 }
 
-variable "cores" {
-  type = number
+variable "control_plane_count" {
+  type        = number
+  default     = 3
+  description = "Number of control plane VMs"
 }
 
-variable "memory" {
-  type = number
+variable "worker_count" {
+  type        = number
+  default     = 3
+  description = "Number of worker VMs"
 }
 
-variable "disk_size" {
-  type = string
+variable "control_plane_vmid_start" {
+  type        = number
+  default     = 701
+  description = "Starting VMID for control plane VMs"
 }
 
-variable "sockets" {
-  type = number
+variable "worker_vmid_start" {
+  type        = number
+  default     = 711
+  description = "Starting VMID for worker VMs"
+}
+
+variable "control_plane_cores" {
+  type        = number
+  default     = 1
+  description = "vCPU cores per control plane VM"
+}
+
+variable "control_plane_memory_mb" {
+  type        = number
+  default     = 4096
+  description = "Memory in MB per control plane VM"
+}
+
+variable "worker_cores" {
+  type        = list(number)
+  default     = [4, 4, 3]
+  description = "vCPU cores for each worker VM"
+
+  validation {
+    condition     = length(var.worker_cores) == var.worker_count
+    error_message = "worker_cores list length must equal worker_count."
+  }
+}
+
+variable "worker_memory_mb" {
+  type        = list(number)
+  default     = [12288, 12288, 12288]
+  description = "Memory in MB for each worker VM"
+
+  validation {
+    condition     = length(var.worker_memory_mb) == var.worker_count
+    error_message = "worker_memory_mb list length must equal worker_count."
+  }
+}
+
+variable "control_plane_disk_size" {
+  type        = string
+  default     = "40G"
+  description = "Disk size for control plane VMs"
+}
+
+variable "worker_disk_size" {
+  type        = string
+  default     = "60G"
+  description = "Disk size for worker VMs"
 }
 
 variable "bridge" {
@@ -55,18 +109,6 @@ variable "pm_api_url" {
   type = string
 }
 
-variable "alpaca_vm_count" {
-  type        = number
-  default     = 1
-  description = "How many Alpaca VMs to create"
-}
-
-variable "llama_vm_count" {
-  type        = number
-  default     = 1
-  description = "How many Llama VMs to create"
-}
-
 variable "SSH_KEY_PUBLIC" {
   type        = string
   description = "Public SSH key injected via cloud-init"