HipcallTts.Providers.Polly (hipcall_tts v0.5.0)
View SourceAmazon Polly Text-to-Speech provider.
Implements HipcallTts.Provider by calling Polly's SynthesizeSpeech endpoint and
signing requests with AWS Signature Version 4 (SigV4).
Streaming is not supported in this MVP (capabilities().streaming == false).