Murf AI Synthesizer support

[nileshmurf]

Murf Synthesizer Integration

This PR adds support for Murf.ai text-to-speech service as a new synthesizer option in Vocode.

Features Added

• New MurfSynthesizer websockets implementation
• MurfSynthesizerConfig with configurable parameters:
  • Voice ID selection
  • Speech rate, pitch, and variation controls
  • Audio format and channel type configuration
  • Style selection (e.g., "Conversational", "Narration", "Inspirational", "Calm" etc )
  • Multi-locale support for voices eg: en-US, en-UK, es-ES etc can be passed in multi_native_locale
• Robust error handling and exponential backoff for WebSocket connections
• Proper context management for streaming sessions

Documentation

• Added Murf to the list of supported synthesizers in documentation
• Created a new quickstart example: murf_streaming_conversation.py
• Updated synthesizer factory to include Murf integration

Usage Example

from vocode.streaming.models.synthesizer import MurfSynthesizerConfig
from vocode.streaming.synthesizer.murf_synthesizer import MurfSynthesizer

synthesizer = MurfSynthesizer(
    MurfSynthesizerConfig(
        api_key=os.getenv("MURF_API_KEY"),
        voice_id="en-US-daniel",
        style="Conversational",
        sampling_rate=16000,
        audio_encoding=AudioEncoding.LINEAR16,
    )
)

Dependencies

• No new dependencies required beyond existing project requirements