dshost-plugin: DSHost Official Remote Cloud Relay Plugin

`dshost-plugin` is the official remote cloud relay plugin for DeepSeek Harness (DSH), designed to solve the challenge of accessing the dsh Web UI in internal network environments. It creates a secure WebSocket tunnel by having the Agent actively connect outward to a relay server, enabling secure remote access with no public IP required. Core features include DSH multi-version compatibility, security mechanisms that comply with trust barriers, mandatory WSS encrypted transmission, and automatic reconnection upon service startup. Installation requires Node.js >= 22.5.0. Users must first obtain a Token from dshost.me, configure it in `cordis.patch.yml`, and restart the service.