feat: Expose the "architecture" variable

main.tf

@@ -55,6 +55,7 @@ module "tailscale_subnet_router" {
   session_logging_ssm_document_name = var.session_logging_ssm_document_name
 
   ami              = var.ami
+  architecture     = var.architecture
   instance_type    = var.instance_type
   max_size         = var.max_size
   min_size         = var.min_size

variables.tf

@@ -96,6 +96,12 @@ variable "ami" {
   EOF
 }
 
+variable "architecture" {
+  default     = "arm64"
+  type        = string
+  description = "The architecture of the AMI (e.g., x86_64, arm64)"
+}
+
 variable "instance_type" {
   default     = "t4g.nano"
   type        = string