Follow-up on @pty819's t2a_v2 endpoint fix:
- Default model: speech-02 -> speech-02-hd (bare 'speech-02' is not in the
supported enum; t2a_v2 rejects it with 400). Official enum: speech-01-hd,
speech-01-turbo, speech-02-hd, speech-02-turbo, speech-2.6-hd/turbo,
speech-2.8-hd/turbo.
- Default voice: female-shaonv -> English_expressive_narrator. The
legacy speech-01-series short ID doesn't resolve cleanly on the
speech-02+ models that are now the default.
- Default base URL: api.minimaxi.com -> api.minimax.io (matches the
canonical host in the published docs; api-uw.minimax.io is the
reduced-latency alt).
- Add GroupId support via tts.minimax.group_id config or MINIMAX_GROUP_ID
env var. Some MiniMax accounts scope TTS requests by group; without it,
requests 401. Only appended when not already in the user's base_url.
Tests rewritten to cover both the default t2a_v2 path (hex-encoded audio
in JSON, nested voice_setting/audio_setting) and the legacy
text_to_speech path (raw audio bytes, flat payload). Adds coverage for
GroupId config/env wiring and error surfacing.
Also adds AUTHOR_MAP entry for pty819's GitHub-noreply email.
7f08cb5941