Nova Sonic transcription & translation

[JGoutin]

Add support for audio transcription and translation using Amazon Nova Sonic as the backend, as an alternative to the existing Amazon Transcribe / Amazon Translate path.

• POST /v1/audio/transcriptions — Nova Sonic backend
• POST /v1/audio/translations — Nova Sonic backend

REF:

• https://docs.aws.amazon.com/nova/latest/userguide/nova-sonic.html