xby-speech-synthesis: Edge TTS-Based Speech Synthesis Service Plugin

The `xby-speech-synthesis` plugin is an MCP server designed specifically for DeepSeek Harness (DSH), integrating Microsoft Edge's high-quality speech synthesis capabilities. It is open source (MIT license), supports multilingual, multi-role dialogue, and audio merging, and requires prior registration on the official Xiaoben Yang website to obtain an API key. Users can install it via CLI and use the `set_xby_apikey` and `generate_speech` commands in the DSH chat window to configure and generate speech.