dsh-canvas-preview: DSH Canvas Preview and Export Plugin

dsh-canvas-preview is a DeepSeek Harness (DSH) plugin maintained by jiuyuechuwuhao and is licensed under the MIT License. This plugin aims to address the inconvenience of previewing, saving, and exporting AI-generated HTML artifacts. By adding a "canvas" view to the DSH session interface, it provides real-time preview and various export functions. Core features include: * An independent canvas tab side-by-side with the chat, supporting real-time preview of a file list on the left and a sandbox on the right; * Automatic scanning of the workspace every 4 seconds to synchronize new artifacts; * A draggable and expandable notification card in the top-right corner displaying real-time rendering thumbnails; * Support for using the native macOS directory picker to "Save As" HTML files; * Providing PNG/JPG bitmaps (using headless Chrome high-definition screenshots) and SVG vector graphics (direct...