dsh-digital-root: Digital Root Calculation

dsh-digital-root is a DeepSeek Harness (DSH) plugin designed to address precision issues that agents may encounter when performing modular arithmetic calculations such as computing digital roots. The plugin pushes the calculation logic down to a local, pure Node.js implementation with no network dependencies, enabling fast and accurate results. Once installed, its tools can be invoked directly, making it suitable for scenarios that require both computational speed and precision.