DeepSeek Harness Plugin: dsh-chat-index-rail (Floating Input Index on the Right Side of the Chat)

This plugin provides a floating table of contents on the right side of long conversation windows, listing user inputs vertically in conversation order. Users can hover to view a preview (15 or 40 characters), click to navigate to the corresponding message, and see the current message automatically highlighted in the TOC while scrolling. Installation requires running npm install in the DSH profile directory and configuring `package.json` and `cordis.patch.yml`. The plugin relies on stable anchors in the DSH Web UI and runs purely client-side, taking effect after a restart.