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

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

packages/vscode/src/networkDefaults.test.ts

@@ -0,0 +1,24 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import * as net from 'node:net';
+import { applyConnectAttemptTimeout } from './networkDefaults';
+
+test('allows slow connections without changing address-family selection', () => {
+  const previousTimeout = net.getDefaultAutoSelectFamilyAttemptTimeout();
+  const previousFamily = net.getDefaultAutoSelectFamily();
+  try {
+    net.setDefaultAutoSelectFamilyAttemptTimeout(250);
+    assert.equal(applyConnectAttemptTimeout(), true);
+    assert.equal(net.getDefaultAutoSelectFamilyAttemptTimeout(), 5_000);
+    assert.equal(net.getDefaultAutoSelectFamily(), previousFamily);
+  } finally {
+    net.setDefaultAutoSelectFamilyAttemptTimeout(previousTimeout);
+  }
+});
+
+test('unsupported runtimes retain their existing behavior', () => {
+  assert.equal(applyConnectAttemptTimeout({}), false);
+  assert.equal(applyConnectAttemptTimeout({
+    setDefaultAutoSelectFamilyAttemptTimeout() { throw new Error('unsupported'); },
+  }), false);
+});