test: verify Puppeteer E2E infrastructure on Windows CI

Integrates `executeBrowserTest` into the `basic/serve` E2E test to
verify browser connectivity against a running HMR server.

Additionally, enables the `basic/serve` test in the Windows CI
workflow to ensure Puppeteer infrastructure stability on Windows.

Author: clydin

.github/workflows/pr.yml

@@ -170,7 +170,7 @@ jobs:
           test_target_name: e2e.esbuild_node22
         env:
           E2E_SHARD_TOTAL: 1
-          TESTBRIDGE_TEST_ONLY: tests/basic/{build,rebuild}.ts
+          TESTBRIDGE_TEST_ONLY: tests/basic/{build,rebuild,serve}.ts
 
   e2e-package-managers:
     needs: build

tests/e2e/tests/basic/serve.ts

@@ -1,6 +1,7 @@
 import assert from 'node:assert/strict';
 import { killAllProcesses } from '../../utils/process';
 import { ngServe } from '../../utils/project';
+import { executeBrowserTest } from '../../utils/puppeteer';
 
 export default async function () {
   // Serve works without HMR
@@ -11,6 +12,8 @@ export default async function () {
   // Serve works with HMR
   const hmrPort = await ngServe('--hmr');
   await verifyResponse(hmrPort);
+
+  await executeBrowserTest({ baseUrl: `http://localhost:${hmrPort}/` });
 }
 
 async function verifyResponse(port: number): Promise<void> {