Wait for login instructions

run.ts

@@ -238,9 +238,17 @@ async function codexDeviceLogin(): Promise<void> {
       new WritableStream({ write: (chunk) => void (shown += chunk) }),
     );
   const drained = Promise.all([collect(login.stdout), collect(login.stderr)]);
+  const status = login.status;
   await new Promise((resolve) => setTimeout(resolve, 3000));
+  while (shown.trim() === "") {
+    const exited = await Promise.race([
+      status.then(() => true),
+      new Promise<boolean>((resolve) => setTimeout(() => resolve(false), 100)),
+    ]);
+    if (exited) throw new Error("AI bot login produced no instructions");
+  }
   await postComment(shown);
-  await Promise.all([login.status, drained]);
+  await Promise.all([status, drained]);
 }
 
 async function runCodex(prompt: string): Promise<string> {