dsh-plug-mcp: MCP Service Manager for DeepSeek Harness

`dsh-plug-mcp` is a DeepSeek Harness plugin that provides a visual interface for MCP service management. Users can search repositories by GitHub Topic via the Web UI, view details, and discover startup hints, with support for one-click installation, removal, and proxy configuration. The plugin automatically writes configuration to the Home layer, uses HMR to enable hot reload, and supports securely integrating and debugging MCP services.