Add configuration files for FastGPT and Xfyun voice services, enhancing LLM service capabilities. Update LLMConfig to include chat_id, variables, detail, and timeout settings. Refactor create_llm_service to support FastGPT integration and adjust pipeline to handle chat_id and greeting prompts. Implement context synchronization for interrupted assistant turns in text streaming.

config/voice-fastgpt.example.json

@@ -0,0 +1,58 @@
+{
+  "server": {
+    "host": "0.0.0.0",
+    "port": 8000,
+    "cors_origins": ["*"]
+  },
+  "audio": {
+    "sample_rate_hz": 16000,
+    "channels": 1,
+    "frame_ms": 20
+  },
+  "session": {
+    "inactivity_timeout_sec": 60
+  },
+  "turn": {
+    "vad": {
+      "confidence": 0.7,
+      "start_secs": 0.2,
+      "stop_secs": 0.6,
+      "min_volume": 0.6
+    },
+    "interruption_min_chars": 3,
+    "interruption_use_interim": true,
+    "user_speech_timeout_sec": 1.0
+  },
+  "agent": {
+    "system_prompt": "FastGPT app owns the system prompt when send_system_prompt is false.",
+    "greeting": "你好",
+    "greeting_mode": "generated"
+  },
+  "services": {
+    "stt": {
+      "provider": "openai",
+      "api_key": "",
+      "base_url": null,
+      "model": "gpt-4o-mini-transcribe",
+      "language": "zh"
+    },
+    "llm": {
+      "provider": "fastgpt",
+      "api_key": "",
+      "base_url": null,
+      "model": "my-voice-app",
+      "chat_id": null,
+      "variables": {},
+      "detail": false,
+      "timeout_sec": 60.0,
+      "send_system_prompt": false
+    },
+    "tts": {
+      "provider": "openai",
+      "api_key": "",
+      "base_url": null,
+      "model": "gpt-4o-mini-tts",
+      "voice": "alloy"
+    }
+  }
+}