[feat] 토론 기록 STT 모드 선택(RPC·Soniox)과 AI 보정 속기록 - #532

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/cache@v4, actions/checkout@v4, actions/setup-node@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

React Hook useEffect has a missing dependency: 'socket'. Either include it or remove the dependency array