Add Cartesia.ai Compatibility

[perinm]

Is your feature request related to a problem? Please describe.

Cartesia.ai is a growing platform that supports WebSocket communication. I’d love to use RealtimeTTS in conjunction with Cartesia.ai for real-time voice interactions, but currently, there’s no direct compatibility.

Describe the solution you'd like

It would be great if RealtimeTTS could support Cartesia.ai’s WebSocket protocol—either by native integration or clear documentation on how to connect the two. I could even create a PR with such changes.

Describe alternatives you’ve considered

NA

Additional context

Cartesia.ai uses standard WebSocket connections, so adapting RealtimeTTS to support its messaging format may be feasible with minimal changes.

Thanks for considering this!

[dkaps125]

I just opened a draft PR for this: #348. I don't have a lot of time to test this on its own or play with additional configuration flexibility but it should be in reasonable enough shape.