curl --request POST \
  --url https://api.shuttleai.com/v1/audio/speech \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "model": "<string>",
  "input": "<string>",
  "voice": "<string>"
}'

{
  "chars": 123,
  "data": {
    "url": "<string>"
  },
  "expiresIn": 123,
  "model": "<string>"
}