dsh-print-dpi: Print Size Calculation Plugin

`dsh-print-dpi` is a plugin for DeepSeek Harness (DSH) that addresses the issue of precise print size calculation when agents handle image or typesetting tasks. The plugin is implemented purely in Node.js, has no network dependencies, and supports precise, parameter-based calculations that return detailed results. The installation command is `dsh plugin add github:uckkk/dsh-print-dpi`. To use it, ensure the environment satisfies the dependencies on `@deepseek-ai/cordis` (^4.0.1) and `@deepseek-ai/dsh-tools` (>=0.1.0-rc.6). It is suitable for scenarios requiring print specifications, resolution, or physical dimension conversions. The source code and details are available in its GitHub repository.