feat: add MiniMax TTS provider support (speech-2.8)
Add MiniMax as a fifth TTS provider alongside Edge TTS, ElevenLabs,
OpenAI, and NeuTTS. Supports speech-2.8-hd (recommended default) and
speech-2.8-turbo models via the MiniMax T2A HTTP API.
Changes:
- Add _generate_minimax_tts() with hex-encoded audio decoding
- Add MiniMax to provider dispatch, requirements check, and Telegram
Opus compatibility handling
- Add MiniMax to interactive setup wizard with API key prompt
- Update TTS documentation and config example
Configuration:
tts:
provider: "minimax"
minimax:
model: "speech-2.8-hd"
voice_id: "English_Graceful_Lady"
Requires MINIMAX_API_KEY environment variable.
API reference: https://platform.minimax.io/docs/api-reference/speech-t2a-http