dsh-md-view: A Secure Markdown Renderer for DSH Client Plugins

`dsh-md-view` is a plugin for DeepSeek Harness (DSH) clients, designed to provide unified, secure, and feature-rich Markdown rendering capabilities. It wraps the native Harness `MarkdownText` primitive into a client-side service `mdView`, supporting GFM, mathematical formulas, footnotes, and Shiki-based code highlighting. The plugin outputs content as React elements to effectively mitigate HTML injection risks and handles the parsing of relative links and images. With no external dependencies, developers can easily invoke it in client plugins via `ctx.mdView.render` or `ctx.mdView.component`, making it suitable for displaying code, logs, documentation, and similar content.