refactor: simplify homelab bootstrap around static IPs and fresh runs

Make Terraform the source of truth for node IPs, remove guest-agent/SSH discovery from the normal workflow path, simplify the bootstrap controller to a fresh-run flow, and swap the initial CNI to Flannel so cluster readiness is easier to prove before reintroducing more complex reconcile behavior.

terraform/variables.tf

@@ -87,6 +87,40 @@ variable "worker_disk_size" {
   description = "Disk size for worker VMs"
 }
 
+variable "network_prefix_length" {
+  type        = number
+  default     = 10
+  description = "CIDR prefix length for static VM addresses"
+}
+
+variable "network_gateway" {
+  type        = string
+  default     = "10.27.27.1"
+  description = "Gateway for static VM addresses"
+}
+
+variable "control_plane_ips" {
+  type        = list(string)
+  default     = ["10.27.27.50", "10.27.27.51", "10.27.27.49"]
+  description = "Static IPv4 addresses for control plane VMs"
+
+  validation {
+    condition     = length(var.control_plane_ips) == var.control_plane_count
+    error_message = "control_plane_ips length must match control_plane_count."
+  }
+}
+
+variable "worker_ips" {
+  type        = list(string)
+  default     = ["10.27.27.47", "10.27.27.46", "10.27.27.48"]
+  description = "Static IPv4 addresses for worker VMs"
+
+  validation {
+    condition     = length(var.worker_ips) == var.worker_count
+    error_message = "worker_ips length must match worker_count."
+  }
+}
+
 variable "bridge" {
   type = string
 }