RealtimeTranslationServerEventSessionInputTranscriptDelta
Returned when optional source-language transcript text is available. This event
is emitted only when audio.input.transcription is configured.Transcript deltas are append-only text fragments. Clients should not insert
unconditional spaces between deltas.
{
"event_id": "string",
"type": "session.input_transcript.delta",
"delta": "string",
"elapsed_ms": 0
}