Adds XAITTSService in the existing xai/tts.py module, alongside the
existing XAIHttpTTSService. Connects to xAI's streaming endpoint at
wss://api.x.ai/v1/tts, streams text.delta chunks up and base64 audio.delta
chunks down on the same connection so audio starts flowing before the full
utterance is synthesized.
Extends InterruptibleTTSService since xAI's protocol is strictly sequential
per connection and exposes neither a cancel verb nor a context ID — the
only way to stop an in-flight utterance is to tear down the WebSocket,
which is exactly what InterruptibleTTSService does on interruption when
the bot is speaking.
Voice, language, codec, and sample_rate are passed as query-string params
at connect time; runtime setting changes reconnect the socket. Defaults to
raw PCM so emitted TTSAudioRawFrame objects need no decoding downstream.
Splits the existing example into voice-xai.py (WebSocket) and
voice-xai-http.py (batch HTTP) so each variant has its own entry point.
Promotes the xai extra to depend on pipecat-ai[websockets-base] since the
new service imports the websockets library.
d8f5c0be71