fix(feishu): await HTTP server close during monitor cleanup

The Feishu monitor's stopFeishuMonitorState() called server.close()
without awaiting the callback, then immediately cleared the Map
entries. This caused:

1. Memory leak — server objects retained after Map.delete()
2. Port binding issues — ports not fully released before restart
3. Resource leak on repeated gateway restarts

Fix: make stopFeishuMonitorState() and stopFeishuMonitor() async,
await server.close() via Promise wrapper before clearing state.
Update all test afterEach hooks to await the cleanup.

Closes #48183

extensions/feishu/src/monitor.startup.test.ts

@@ -44,8 +44,8 @@ async function waitForStartedAccount(started: string[], accountId: string) {
   }
 }
 
-afterEach(() => {
-  stopFeishuMonitor();
+afterEach(async () => {
+  await stopFeishuMonitor();
 });
 
 describe("Feishu monitor startup preflight", () => {

extensions/feishu/src/monitor.state.ts

@@ -132,13 +132,15 @@ export function recordWebhookStatus(
   });
 }
 
-export function stopFeishuMonitorState(accountId?: string): void {
+export async function stopFeishuMonitorState(accountId?: string): Promise<void> {
   if (accountId) {
     wsClients.delete(accountId);
     const server = httpServers.get(accountId);
     if (server) {
-      server.close();
       httpServers.delete(accountId);
+      await new Promise<void>((resolve) => {
+        server.close(() => resolve());
+      });
     }
     botOpenIds.delete(accountId);
     botNames.delete(accountId);
@@ -146,10 +148,16 @@ export function stopFeishuMonitorState(accountId?: string): void {
   }
 
   wsClients.clear();
+  const closePromises: Promise<void>[] = [];
   for (const server of httpServers.values()) {
-    server.close();
+    closePromises.push(
+      new Promise<void>((resolve) => {
+        server.close(() => resolve());
+      }),
+    );
   }
   httpServers.clear();
+  await Promise.all(closePromises);
   botOpenIds.clear();
   botNames.clear();
 }

extensions/feishu/src/monitor.ts

@@ -90,6 +90,6 @@ export async function monitorFeishuProvider(opts: MonitorFeishuOpts = {}): Promi
   await Promise.all(monitorPromises);
 }
 
-export function stopFeishuMonitor(accountId?: string): void {
-  stopFeishuMonitorState(accountId);
+export async function stopFeishuMonitor(accountId?: string): Promise<void> {
+  await stopFeishuMonitorState(accountId);
 }

extensions/feishu/src/monitor.webhook-e2e.test.ts

@@ -58,8 +58,8 @@ async function postSignedPayload(url: string, payload: Record<string, unknown>)
   });
 }
 
-afterEach(() => {
-  stopFeishuMonitor();
+afterEach(async () => {
+  await stopFeishuMonitor();
 });
 
 describe("Feishu webhook signed-request e2e", () => {

extensions/feishu/src/monitor.webhook-security.test.ts

@@ -35,9 +35,9 @@ import {
   stopFeishuMonitor,
 } from "./monitor.js";
 
-afterEach(() => {
+afterEach(async () => {
   clearFeishuWebhookRateLimitStateForTest();
-  stopFeishuMonitor();
+  await stopFeishuMonitor();
 });
 
 describe("Feishu webhook security hardening", () => {