dsh-plugin-msg-nav: DSH Dialogue Node Navigation Bar Plugin

dsh-plugin-msg-nav is a lightweight navigation plugin for DeepSeek Harness (DSH), designed to address the difficulty of locating old messages in lengthy conversations. It renders a vertical node string along the right edge of the conversation area, mapping each authentic user message to an independent node. Users can hover to preview message content (the panel displays up to 10 items with scroll support) and click to smoothly jump to and highlight the corresponding message. The plugin features a smart loading mechanism: while the session projection covers all user messages, clicking on unloaded older messages will automatically fetch historical data on demand. The node string automatically hides when there are fewer than 2 user messages, the session is empty, or the view is not in conversation mode. This plugin is based on the MIT license, requires a restart or page refresh to take effect after installation, and is maintained by SherUnlocked-4869, supporting React 18.2.0 and above.