Azure Cognitive Services subscription key.
Sent as the Ocp-Apim-Subscription-Key header — this is Azure's
standard authentication mechanism for Cognitive Services REST APIs.
Obtain from the Azure portal under your Speech resource's "Keys and Endpoint".
Azure region where the Speech resource is deployed, e.g. 'eastus',
'westeurope', 'southeastasia'.
The region determines the REST endpoint hostname:
https://{region}.stt.speech.microsoft.com
Optional fetchCustom fetch implementation for dependency injection in tests.
Optional init: RequestInitOptional init: RequestInitglobalThis.fetch
Configuration for the AzureSpeechSTTProvider.
See