feat(release): add phase10 tests, smoke load script, release checklist, and onboarding simulator flow

Backend/scripts/load-smoke.ts

@@ -0,0 +1,26 @@
+const baseUrl = process.env.LOAD_BASE_URL ?? 'http://localhost:3000';
+const rounds = Number(process.env.LOAD_ROUNDS ?? 25);
+
+const run = async () => {
+  const start = Date.now();
+
+  for (let i = 0; i < rounds; i += 1) {
+    const [live, ready, metrics] = await Promise.all([
+      fetch(`${baseUrl}/ops/live`),
+      fetch(`${baseUrl}/ops/ready`),
+      fetch(`${baseUrl}/ops/metrics`),
+    ]);
+
+    if (!live.ok || !ready.ok || !metrics.ok) {
+      throw new Error(`Smoke load failed at round ${i + 1}`);
+    }
+  }
+
+  const totalMs = Date.now() - start;
+  console.log(`Completed ${rounds} rounds in ${totalMs}ms`);
+};
+
+run().catch((error) => {
+  console.error(error);
+  process.exit(1);
+});