List voices

{
  "items": [
    {
      "id": "550e8400-e29b-41d4-a716-446655440000",
      "user_id": "550e8400-e29b-41d4-a716-446655440000",
      "label": "My Voice",
      "description": "This is a description",
      "type": "voice_azure",
      "voice_name": "en-US-JennyNeural",
      "pitch": 1,
      "rate": 1
    }
  ],
  "page": 123,
  "size": 123,
  "has_more": true,
  "total": 123,
  "total_is_estimated": true
}