Cartesia TTS using Flutter

Minimal example of using cartesia tts to produce text-to-speech audio and play it using the flutter_soloud Flutter plugin.

The workflow:

• Authenticate with the Cartesia API
• Setup a text-to-speech message to request PCM audio to Cartesia and a corresponding flutter_soloud stream with the same format
• Request text-to-speech audio
• Play the audio at first chunk received

Note: replace the cartesiaApiKey with your Cartesia API key in main.dart. Note2: no stream buffering management. If the data comes slower than the rate of the flutter_soloud stream, the audio could have gaps.