fix(mcp): await failed transport cleanup on Windows

Wait for failed MCP transport cleanup before command exit so targeted live checks do not crash on Windows.

Co-Authored-By: Claude <noreply@anthropic.com>

src/services/mcp/client.test.ts

@@ -0,0 +1,48 @@
+import assert from 'node:assert/strict'
+import test from 'node:test'
+
+import { cleanupFailedConnection } from './client.js'
+
+test('cleanupFailedConnection awaits transport close before resolving', async () => {
+  let closed = false
+  let resolveClose: (() => void) | undefined
+
+  const transport = {
+    close: async () =>
+      await new Promise<void>(resolve => {
+        resolveClose = () => {
+          closed = true
+          resolve()
+        }
+      }),
+  }
+
+  const cleanupPromise = cleanupFailedConnection(transport)
+
+  assert.equal(closed, false)
+  resolveClose?.()
+  await cleanupPromise
+  assert.equal(closed, true)
+})
+
+test('cleanupFailedConnection closes in-process server and transport', async () => {
+  let inProcessClosed = false
+  let transportClosed = false
+
+  const inProcessServer = {
+    close: async () => {
+      inProcessClosed = true
+    },
+  }
+
+  const transport = {
+    close: async () => {
+      transportClosed = true
+    },
+  }
+
+  await cleanupFailedConnection(transport, inProcessServer)
+
+  assert.equal(inProcessClosed, true)
+  assert.equal(transportClosed, true)
+})