[FEATURE] Support for TTS and voice api

[amaghzaz-y]

Confirmation of Request Source

• I confirm that this feature request is for the xAI SDK Python library (e.g., client features, SDK methods, or documentation) and not for the xAI API itself (e.g., model capabilities or API changes).

Describe the feature you'd like

Adding support for Voice API and TTS

Additional Context

No response

[Omar-V2]

Yes, coming shortly