dsh-client-background: Replace the DSH Web Client Background with a Random Unsplash Wallpaper

This plugin is designed to provide dynamic backgrounds for the DeepSeek Harness (DSH) Web client, using curated Unsplash images to replace the plain default background. Maintained by `imcp-pro`, it relies only on native browser APIs and has no framework dependencies. Core features include a curated wallpaper carousel, a runtime enable/disable toggle, automatic update checks, and no framework coupling. When installing, be aware of pnpm version compatibility issues. Users can customize the image rotation interval and update check settings via the settings panel. The plugin automatically follows theme switches, but background scrolling compatibility issues exist on iOS Safari.