Integrate google-camb-vertex TTS

[Saransh-Shankar]

Add Google Vertex CAMB (MARS7) TTS Service

• Integrates CAMB.AI's MARS7 text-to-speech model deployed on Google Cloud Vertex AI with Vocode, providing high-quality speech synthesis with voice cloning capabilities.

Key Features

• High-quality TTS: Uses MARS7 model for natural-sounding speech synthesis
• Voice cloning: Support for reference audio to clone voices
• Multilingual support: Multiple languages including en-us, es-es, de-de, fr-fr, ja-jp, ko-kr, zh-cn
• Async implementation: Uses async predict endpoint to prevent blocking the event loop