fix: de_foreground_app fallback mFocusedApp（MIUI 过渡期 mCurrentFocus=null 时前台解析为空）

mcp_server/direct_ops.py

@@ -40,10 +40,14 @@ def stop_app(serial, package):
 
 
 def foreground_app(serial):
-    """当前前台 App 包名（dumpsys window 解析；失败返回空）。"""
-    out = _adb(serial, "dumpsys", "window", timeout=15)
-    m = re.search(r"mCurrentFocus=.*?([\w.]+)/", out or "")
-    return m.group(1) if m else ""
+    """当前前台 App 包名（dumpsys window；mCurrentFocus 为空时 fallback mFocusedApp）。"""
+    out = _adb(serial, "dumpsys", "window", timeout=15) or ""
+    m = re.search(r"mCurrentFocus=.*?([\w.]+)/", out)
+    if m:
+        return m.group(1)
+    # 部分 MIUI 焦点在 IME/过渡时 mCurrentFocus=null，用 mFocusedApp 兜底
+    m2 = re.search(r"mFocusedApp=.*?([\w.]+)/", out)
+    return m2.group(1) if m2 else ""
 
 
 def list_apps(serial, keyword=""):