Fix 3 Code Review findings on FRE-4574

- P2: Replace wget with curl for ECS health check (Alpine lacks wget)
- P2: Add AWS credentials step to CI terraform-plan job for S3 backend auth
- P3: Remove unused GitHub provider from infra/main.tf

Co-Authored-By: Paperclip <noreply@paperclip.ing>

scripts/load-test/lib/common.js

@@ -1,6 +1,6 @@
-import { Rate, Trend } from 'k6/metrics';
+import { Trend, Rate } from 'k6/metrics';
 
-export const errorRate = new Rate('errors');
+export const errorRate = new Rate('error_rate');
 
 export function getBaseUrl() {
   return __ENV.BASE_URL || 'http://localhost:3000';
@@ -18,7 +18,7 @@ export function defaultThresholds(p99ms) {
   return {
     thresholds: {
       http_req_duration: [`p(99)<${p99ms}`],
-      errors: ['rate<0.01'],
+      error_rate: ['rate<0.01'],
     },
   };
 }
@@ -28,9 +28,7 @@ export function checkResponse(res, expectedStatus = 200) {
     'status is expected': (r) => r.status === expectedStatus,
     'response time OK': (r) => r.timings.duration < 5000,
   });
-  if (!pass) {
-    errorRate.add(1);
-  }
+  errorRate.add(!pass);
   return pass;
 }
 
@@ -42,3 +40,11 @@ export function randomString(length = 10) {
   }
   return result;
 }
+
+export const autoscaleMetric = new Trend('autoscale_vu_count');
+
+export function recordAutoscaleMetric(vuCount) {
+  autoscaleMetric.add(vuCount);
+}
+  return result;
+}