feat: AI 目标设备必选 + 设备任务占用锁——①前端新增「🎯 目标设备」选择器（在线设备含型号，任务运行中的设备禁选），发送必须选定设备，AI 只操作你指定的设备；②/api/agent/run 校验：serial 不在池/离线/任务 running-connecting → 拒绝（409 提示任务名）；③MCP 11 个写工具加 busy 锁（_ensure_device_free，5s 缓存）：任务运行中的设备 AI 一律拒绝，AI 不与任务抢设备（外部 MCP 客户端同样受保护）；④运行状态端点 GET /api/agent/run + 前端 8s 轮询：多人/多窗口能看到运行中任务（发起时间/任务/设备）并可停止（stop 加确认）；未选设备直接 400 引导请选择设备，去掉模型自己乱挑设备的行为

mcp_server/mcp_server.py

@@ -52,6 +52,32 @@ def _check_write():
         raise PlatformError("write_disabled", "写操作未启用（MCP_ALLOW_WRITE=1 开启）")
 
 
+# 设备任务占用锁：serial -> (ts, worker_status, task_job)。AI 写操作前检查，
+# 任务 running/connecting 的设备拒绝操作（AI 不与任务抢设备）。5s 缓存。
+_busy_cache = {}
+
+
+def _ensure_device_free(serial):
+    """写操作前检查设备是否有任务在跑（worker running/connecting → 拒绝）。"""
+    import time
+    now = time.time()
+    c = _busy_cache.get(serial)
+    if not c or now - c[0] > 5:
+        try:
+            devs = platform().list_devices()
+            info = next((d for d in devs if d.get("serial") == serial), {})
+            c = (now, info.get("worker_status") or "idle",
+                 info.get("task_job") or "")
+            _busy_cache[serial] = c
+        except Exception:
+            return  # 状态查询失败不阻塞（操作失败会另行报错）
+    if c[1] in ("running", "connecting"):
+        raise PlatformError(
+            "device_busy",
+            f"设备正在执行任务「{c[2] or '未知'}」——AI 不与任务抢设备，"
+            f"任务结束后才能操作（可在平台任务页先停止任务）")
+
+
 def _to_native(serial, x, y):
     """截图坐标 → 设备原生坐标（按最近一次截图的比例换算）。"""
     c = _coord.get(serial)
@@ -138,6 +164,7 @@ def de_tap(serial: str, x: int, y: int) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if x < 0 or y < 0:
             raise PlatformError("invalid_param", "坐标不能为负")
         nx, ny = _to_native(serial, x, y)
@@ -160,6 +187,7 @@ def de_swipe(serial: str, x1: int, y1: int, x2: int, y2: int,
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         nx1, ny1 = _to_native(serial, x1, y1)
         nx2, ny2 = _to_native(serial, x2, y2)
         platform().swipe(serial, nx1, ny1, nx2, ny2, duration)
@@ -217,6 +245,7 @@ def de_tap_element(serial: str, by: str, value: str, index: int = 1) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if by not in ("text", "id", "desc", "text_contains", "desc_contains"):
             raise PlatformError("invalid_param",
                                 "by 可选 text/id/desc/text_contains/desc_contains")
@@ -270,6 +299,7 @@ def de_wake(serial: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         platform().wake(serial)
     except PlatformError as e:
         return _err(e)
@@ -283,6 +313,7 @@ def de_press_key(serial: str, key: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if key not in _KEYS:
             raise PlatformError("invalid_param", f"不支持的按键: {key}（可选 {_KEYS}）")
         platform().press_key(serial, key)
@@ -299,6 +330,7 @@ def de_open_app(serial: str, package: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if not package:
             raise PlatformError("invalid_param", "缺少包名")
         from mcp_server import direct_ops
@@ -317,6 +349,7 @@ def de_stop_app(serial: str, package: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if not package:
             raise PlatformError("invalid_param", "缺少包名")
         from mcp_server import direct_ops
@@ -350,6 +383,7 @@ def de_type_text(serial: str, text: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if not text:
             raise PlatformError("invalid_param", "内容为空")
         from mcp_server import direct_ops
@@ -370,6 +404,7 @@ def de_set_clipboard(serial: str, text: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if not text:
             raise PlatformError("invalid_param", "内容为空")
         from mcp_server import direct_ops
@@ -390,6 +425,7 @@ def de_sleep(serial: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         platform().sleep(serial)
     except PlatformError as e:
         return _err(e)
@@ -429,6 +465,7 @@ def de_tap_text(serial: str, text: str) -> dict:
     try:
         _check_write()
         serial = _check_serial(serial)
+        _ensure_device_free(serial)
         if not text or len(text) > 100:
             raise PlatformError("invalid_param", "text 不能为空且 ≤100 字符")
         res = platform().tap_text(serial, text)