dsh-interaction-design: Interaction Design Theory Reference

The DeepSeek Harness (DSH) plugin `dsh-interaction-design` is designed to provide developers with a local reference for interaction design theory, addressing the need to access theoretical resources offline. Built in pure Node.js with no external service dependencies, it supports quick command-based installation and local loading. It is suitable for developers who need to reference design theory to inform agent decision-making, but the source code and license should be reviewed before installation.