DeepSeek Harness Plugin: dsh-plugin-slashx-gateway

`dsh-plugin-slashx-gateway` is a DeepSeek Harness plugin that connects a Harness instance to the SlashX protocol and runs as a compliant gateway service. It supports request processing, rich media responses, asynchronous callbacks, and security mechanisms. Installation requires Node.js 22.19+ and the official `web` profile, along with configuration of a random token. The plugin registers the `slashx_deliver` tool with Harness, allowing agents to return rich media content such as text, images, files, quotes, cards, and buttons. It is suitable for deployment and interaction through the SlashX ecosystem.