dsh-prompt-rail: Vertical Prompt Quick-Jump Bar for DSH Web Sessions

`dsh-prompt-rail` is an MIT-licensed plugin for the DeepSeek Harness (DSH) Web session view, designed to address the difficulty of locating ordinary user prompts in long conversations. This plugin adds a vertical quick-jump bar beside the sidebar, displaying each loaded ordinary user prompt as an individual marker. It supports hover preview and click-to-scroll navigation while filtering out non-user messages such as assistant and tool messages, thereby improving search efficiency. To install, place the plugin directory in the `plugins` folder within the Harness root directory. Windows users can use a batch script for one-click installation and restart, while macOS/Linux users need to run the Node installation script and start the Web service. In the development environment, it is recommended to work in a parallel checkout.