fix(opengb): opengb. -> backend. (#919)

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## Changes

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infra/tf/dns/cert_packs.tf

@@ -1,7 +1,7 @@
 locals {
 	# Required if:
 	#
-	# - OpenGB is enabled so requires access to `*.opengb.{domain_main}`
+	# - OpenGB is enabled so requires access to `*.backend.{domain_main}`
  	# - Main domain is not at the root of the zone, we need to provide a cert pack for the domain.
 	# - Using the old `{service}.api.{domain}` format, which requires two levels of subdomains.
  	needs_main_cert_pack = var.opengb_enabled || var.dns_deprecated_subdomains || data.cloudflare_zone.main.name != var.domain_main
@@ -41,8 +41,7 @@ resource "cloudflare_certificate_pack" "main" {
 				"*.api.${var.domain_main}",
 			],
 			var.opengb_enabled ? [
-				"*.opengb.${var.domain_main}",
-				"db.opengb-internal.${var.domain_main}"
+				"*.backend.${var.domain_main}",
 			] : []
 		])
 	)))

infra/tf/tls/cloudflare.tf

@@ -65,8 +65,7 @@ resource "cloudflare_origin_ca_certificate" "rivet_gg" {
 			"api.${var.domain_main}",
 		],
 		var.opengb_enabled ? [
-			"*.opengb.${var.domain_main}",
-			"db.opengb-internal.${var.domain_main}"
+			"*.backend.${var.domain_main}",
 		] : []
 	])
 	request_type = "origin-rsa"

lib/bolt/core/src/dep/terraform/gen.rs

@@ -313,11 +313,7 @@ async fn vars(ctx: &ProjectContext) {
 		// OpenGB
 		extra_dns.push(json!({
 			"zone_name": "main",
-			"name": format!("*.opengb.{domain_main}"),
-		}));
-		extra_dns.push(json!({
-			"zone_name": "main",
-			"name": format!("db.opengb-internal.{domain_main}"),
+			"name": format!("*.backend.{domain_main}"),
 		}));
 
 		// Add services

lib/util/core/src/route.rs

@@ -108,7 +108,7 @@ pub fn opengb_env(project_name_id: &str, env_name_id: &str) -> GlobalResult<Stri
 	let domain_main = unwrap!(domain_main(), "dns not enabled");
 
 	Ok(format!(
-		"https://{}--{}.opengb.{}/",
+		"https://{}--{}.backend.{}/",
 		project_name_id,
 		env_name_id,
 		domain_main,