dsh-xiangqi-mate: A Chinese Chess Plugin for Human vs. AI Play on DeepSeek Harness

`dsh-xiangqi-mate` is a Xiangqi (Chinese chess) human-versus-AI plugin for DeepSeek Harness (DSH), developed by user `lpeixin`. It addresses limitations of existing plugins, such as restricted functionality or frequent interruptions, enabling smooth in-session play. It features zero dependencies, automatic fallback to a local engine, universally compatible move notation, and a multilingual UI. It can be installed through `plugin_manager` and supports mouse drag-and-drop or command-line interaction. Users can configure the opponent as a model or a local engine. If the model times out or violates the rules, the plugin automatically switches to the local engine so the game can continue, making it an ideal choice for building a robust play environment.