dsh-image-router: Enabling Text-Only Models to “See” Images

The DeepSeek Harness plugin `dsh-image-router` addresses the inability of text-only models to process image inputs. Before prompt admission, it leverages a vision model to automatically convert images into text descriptions, while keeping the session model selection unchanged. Users can paste images into a conversation for automatic text conversion or use the `describe_image` tool to analyze local images. The plugin supports configuring an existing vision model or a custom endpoint, and features comprehensive audit logs, test coverage, and a graphical configuration interface. It requires DSH 0.1.5-rc.1 and Node.js ≥ 20.