dsh-image-plugins: Integrating Image Understanding and Generation for DeepSeek Harness

The DeepSeek Harness multimodal plugin, dsh-image-plugins, provides image understanding and generation capabilities for the DSH Web interface. The plugin consists of two independent tools, understand_image and generate_image, which respectively support reading workspace images and returning text descriptions, as well as generating and saving images based on prompts. The plugin supports both OpenAI-compatible endpoints and the native DashScope API, though DashScope image generation requires using the native Model Studio API to avoid 404 errors. After installation, the vision and image functions must be enabled separately via the Web settings panel or configuration file, and the corresponding baseUrl, apiKey, and model must be configured. Keys support both plaintext and environment variables.