xAI's /v1/stt now answers HTTP 400 "Field 'language' is required when
'format' is true", so every transcription with stt.language "" (auto-detect)
failed on both the server path and the Desktop client-direct path. Send the
inverse-text-normalization flag only when a language is resolved; the model
field is still always named. Comments updated: the server default moved from
grok-voice-transcribe-1.0 to 2.0 between Sep 17 and Sep 21, so the pin is
about determinism and a 1.0 rollback knob, not about escaping a 1.0 default.
Live: auto-detect on origin/main -> HTTP 400; with this change -> transcript
returned for 2.0 and pinned 1.0; language=en still sends format=true.
(cherry picked from commit 1ff4887819a12a5e37e9cbea7f31b5cc6b040857)
d1152d797c