DeepSeek Harness Plugin: Indexing and Locating Messages in the Chat Window

`dsh-msg-index` is a client plugin for DeepSeek Harness, designed to address the inefficiency of revisiting messages in long conversations. It provides user message indexing, smooth click-based navigation, real-time search highlighting, and paginated loading of conversation history through a floating button in the bottom-right corner. Easy to install, it supports searching by index number or content, significantly improving the experience of locating specific prompts or responses in long conversations.