feat(cookie-gate): 补充 cookie_gate 网关模块与 deploy/watchdog 保活脚本

cookie_gate.py(账号三级门控/阻断记录 pending_reruns/恢复重跑管理器)为此前
接线提交遗漏的模块文件；deploy/watchdog 为控制台与调度器的进程外保活脚本。

deploy/watchdog/start-keepalive.vbs

@@ -0,0 +1,5 @@
+' GYXX Flow 保活登录自启动：无窗口启动 deploy/watchdog/gyxx_keepalive.py，
+' 由它负责拉起控制台（含进程内自检看门狗）与调度器。
+' 安装：复制到 %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup\
+CreateObject("WScript.Shell").Run _
+    """D:\gyxx-flow\.venv\Scripts\pythonw.exe"" ""D:\gyxx-flow\deploy\watchdog\gyxx_keepalive.py""", 0, False