dsh-vision-adapter: Adding drag-and-drop image recognition capability to DeepSeek Harness

dsh-vision-adapter is a DSH-exclusive plugin maintained by motongv (MIT License) that solves the issue where DSH text models cannot recognize images. The chat interface remains unchanged; images are first converted into text descriptions by the vision model, which is then submitted to DeepSeek for reasoning and response. The plugin acts as an in-process HTTP bridge within DSH to register vision.