sage-guikit: DSH Desktop Control Toolkit

`sage-guikit` is a Windows desktop control toolkit designed specifically for DeepSeek Harness (DSH), aiming to provide an Agent with the abilities to "see" and "act." This plugin packages Windows desktop control capabilities into a profile bundle, offering screen monitoring, screenshots, mouse/keyboard interaction, window management, and structured querying and validation based on UI Automation. To install it, add the plugin as a bundle in `package.json` and restart the service. The plugin defines three strict spatial contracts: virtual desktop physical coordinates, image pixel coordinates, and window-local coordinates, and provides 13 model tools, including click, typing, key presses, dragging, and semantic validation. It supports Windows only.