DSH Web Window Companion Plugin: App-Mode Window Opens a Web GUI, and Closing It Gracefully Stops the Service

`dsh-web-window-companion` is a DeepSeek Harness (DSH) plugin designed to switch the Web profile to desktop app mode. It uses Edge or Chrome App mode to open standalone windows, features zero dependencies and zero configuration, supports stopping the service when the window is closed, and automatically detects the browser. After installation, simply run `dsh web` to start it. It is suitable for use cases that require quick start and stop without interfering with daily browsing. Note that it should not be enabled at the same time as `dsh-win-quick-launcher`.