dsh-sick-leave-pay: Precise Calculation of Sick Leave Pay

The `dsh-sick-leave-pay` plugin provides local sick-leave pay calculation for DeepSeek Harness (DSH) without requiring an internet connection. Maintained by `istone`, its core functionality is to accurately calculate sick-leave pay based on the provided parameters via the registered `sick_leave_pay` tool, along with the applicable legal basis. Before installation, ensure that `@deepseek-ai/cordis` is version `^4.0.1` and `@deepseek-ai/dsh-tools` is version `>=0.1.0-rc.6`. As a pure Node.js implementation, it ensures stable operation and accurate calculations in offline environments.