feat: 添加 TTS 语音名称常量并更新 TTS 服务逻辑

- 在 constants.py 中新增 TTS_VOICE_NAMES 列表，包含多个语音名称。
- 更新 tts_service.py 中的语音配置逻辑，确保使用请求中的语音名称（如果有效），否则回退到默认配置。

app/core/constants.py

@@ -77,3 +77,14 @@ DEFAULT_SAFETY_SETTINGS = [
         {"category": "HARM_CATEGORY_DANGEROUS_CONTENT", "threshold": "OFF"},
         {"category": "HARM_CATEGORY_CIVIC_INTEGRITY", "threshold": "BLOCK_NONE"},
     ]
+
+TTS_VOICE_NAMES = [
+    "Zephyr", "Puck", "Charon", "Kore",
+    "Fenrir", "Leda", "Orus", "Aoede",
+    "Callirhoe", "Autonoe", "Enceladus", "Iapetus",
+    "Umbriel", "Algieba", "Despina", "Erinome",
+    "Algenib", "Rasalgethi", "Laomedeia", "Achernar",
+    "Alnilam", "Schedar", "Gacrux", "Pulcherrima",
+    "Achird", "Zubenelgenubi", "Vindemiatrix", "Sadachbia",
+    "Sadaltager", "Sulafat"
+]

app/service/tts/tts_service.py

@@ -8,6 +8,7 @@ from typing import Optional
 from google import genai
 
 from app.config.config import settings
+from app.core.constants import TTS_VOICE_NAMES
 from app.database.services import add_error_log, add_request_log
 from app.domain.openai_models import TTSRequest
 from app.log.logger import get_openai_logger
@@ -47,7 +48,7 @@ class TTSService:
                     "speech_config": {
                         "voice_config": {
                             "prebuilt_voice_config": {
-                                "voice_name": settings.TTS_VOICE_NAME
+                                "voice_name": request.voice if request.voice in TTS_VOICE_NAMES else settings.TTS_VOICE_NAME
                             }
                         }
                     },