dsh-web-restart: Ensure/Restart DSH Web Service

The DeepSeek Harness plugin `dsh-web-restart` is designed to address the “suicide restart” issue caused by Web services running within the Agent process tree. It uses WMI on Windows to create a standalone process, or detached mode on non-Windows platforms, ensuring that the service automatically recovers when it crashes or can be restarted via a flag. The plugin supports `ensure` and `rotate` modes and requires DSH version 0.1.0-rc.6 or later.