add Terraform + Ansible infrastructure for GCP deployment

Provisions e2-micro VM (us-east1-b, free tier) with static IP, SSH and
web firewall rules, Docker + Caddy startup script, and IAM bindings for
Firestore and GCS access via ADC. Imports existing drb-calls bucket and
c2-server Firestore database into state. Ansible roles handle first-time
setup (swap, docker group) and all subsequent deploys via rsync + docker
compose, with secrets managed via Ansible Vault. DNS stays on AWS Route 53.

infra/variables.tf

@@ -20,11 +20,6 @@ variable "domain" {
   type        = string
 }
 
-variable "dns_zone_name" {
-  description = "Cloud DNS managed zone name"
-  type        = string
-}
-
 variable "machine_type" {
   description = "Compute Engine machine type"
   type        = string
@@ -46,3 +41,26 @@ variable "allowed_ssh_cidrs" {
   description = "CIDR ranges allowed to SSH to the VM (your IP + Gitea runner)"
   type        = list(string)
 }
+
+variable "audio_bucket_name" {
+  description = "Existing GCS bucket name for call audio recordings"
+  type        = string
+}
+
+variable "audio_bucket_location" {
+  description = "GCS bucket location — must match the existing bucket's location exactly"
+  type        = string
+  default     = "US-CENTRAL1"
+}
+
+variable "firestore_database" {
+  description = "Firestore database ID (e.g. c2-server)"
+  type        = string
+  default     = "c2-server"
+}
+
+variable "firestore_location" {
+  description = "Firestore multi-region location (nam5 = us-central, eur3 = europe)"
+  type        = string
+  default     = "nam5"
+}