fix(network): apply connection timeout in server and extension hosts

Complete the runtime entrypoints from #3404 without changing address-family selection.

packages/web/server/lib/network-defaults.test.js

@@ -1,9 +1,25 @@
 import { describe, expect, it, vi } from 'vitest';
 import net from 'node:net';
+import { spawnSync } from 'node:child_process';
 
 import { applyConnectAttemptTimeout, CONNECT_ATTEMPT_TIMEOUT_MS } from './network-defaults.js';
 
 describe('applyConnectAttemptTimeout', () => {
+  it('initializes the server entrypoint in a fresh Node process', () => {
+    const serverUrl = new URL('../index.js', import.meta.url).href;
+    const result = spawnSync('node', ['--input-type=module', '--eval', `
+      import net from 'node:net';
+      import assert from 'node:assert/strict';
+      const family = net.getDefaultAutoSelectFamily();
+      net.setDefaultAutoSelectFamilyAttemptTimeout(250);
+      await import(${JSON.stringify(serverUrl)});
+      assert.equal(net.getDefaultAutoSelectFamilyAttemptTimeout(), 5000);
+      assert.equal(net.getDefaultAutoSelectFamily(), family);
+      process.exit(0);
+    `], { encoding: 'utf8', timeout: 15_000, windowsHide: true });
+    expect(result.status, result.stderr).toBe(0);
+  });
+
   it('raises the per-attempt connect timeout on runtimes that expose the setter', () => {
     const previous = net.getDefaultAutoSelectFamilyAttemptTimeout();
     try {