dsh-voice-by-edge: Add Voice Communication Practice Mode for DSH Web Pages

dsh-voice-by-edge is a speech practice plugin designed specifically for DSH Web pages, aiming to enhance the listening and speaking practice experience by integrating Text-to-Speech (TTS) reading and Speech-to-Text (STT) voice input. This plugin is based on the MIT license and maintained by astr0mfly; its core features include bilingual colloquial short sentence responses, automatic dialogue reading, microphone real-time voice input, and automatic sending. TTS prioritizes Microsoft Edge Neural Voice and falls back to browser local synthesis if unavailable, while STT relies on the browser's Web Speech API. Users can install it via the `dsh plugin add` command (requiring the `msedge-tts` build script to be allowed) and enable it after restarting. It covers use cases such as speed adjustment (0.75x-1.5x), sentence-by-sentence reading, and shadowing.