e00b965406
The xAI TTS REST endpoint (POST /v1/tts) accepts 'speed' (0.7-1.5) and 'optimize_streaming_latency' (0/1/2) parameters, but the Hermes built-in xAI provider was reading neither from config nor sending either in the request body. Add them as tts.xai.speed and tts.xai.optimize_streaming_latency config knobs (with global tts.speed / tts.optimize_streaming_latency fallbacks). - speed: float, clamped to 0.7-1.5. 1.0 (the API default) is omitted from the request body to preserve the existing minimal-payload contract. - optimize_streaming_latency: int, clamped to 0-2. 0 (best quality, the API default) is omitted from the request body. Resolver order: tts.xai.<knob> overrides the global tts.<knob>.