dsh-group: Array Grouping Plugin for DeepSeek Harness

DeepSeek Harness (DSH) offers a lightweight array grouping plugin, `dsh-group`. Built on pure Node.js with no network dependencies, it helps developers group list or array data based on specific conditions. Users can install it via a command and directly invoke its features in workflows. The plugin is open source under the MIT License and is suitable for scenarios involving list data processing.