dsh-output-styles: DeepSeek Harness Output Styles Management Plugin

The `dsh-output-styles` plugin for DeepSeek Harness (DSH) enables consistent control over output formatting in multi-agent scenarios. It adds an “Output Styles” page to the DSH Web settings, offering five built-in styles and a custom option. Users can configure styles via Markdown directives; these styles are injected in real time into the agent’s system prompt and persisted, with support for pasting file contents. The plugin requires Node.js 20+, supports dynamic installation within a session, and only supports a flat Frontmatter format.