更新配置文件，重构工作流管理逻辑，调整国际化文件文职，优化图像生成和文本转语音服务的工作流解析，确保默认工作流配置必填，调整前端工作流选择逻辑。

reelforge/config/manager.py

@@ -96,7 +96,7 @@ class ConfigManager:
     def get_image_config(self) -> dict:
         """Get image configuration as dict"""
         return {
-            "default": self.config.image.default,
+            "default_workflow": self.config.image.default_workflow,
             "comfyui_url": self.config.image.comfyui_url,
             "runninghub_api_key": self.config.image.runninghub_api_key,
             "prompt_prefix": self.config.image.prompt_prefix,

reelforge/config/schema.py

@@ -15,12 +15,16 @@ class LLMConfig(BaseModel):
 
 class TTSConfig(BaseModel):
     """TTS configuration"""
-    default: str = Field(default="edge", description="Default TTS workflow")
+    model_config = {"populate_by_name": True}  # Allow both field name and alias
+    
+    default_workflow: str = Field(default="edge", description="Default TTS workflow", alias="default")
 
 
 class ImageConfig(BaseModel):
     """Image generation configuration"""
-    default: str = Field(default="image_default.json", description="Default image workflow")
+    model_config = {"populate_by_name": True}  # Allow both field name and alias
+    
+    default_workflow: str = Field(default=None, description="Default image workflow (required, no fallback)", alias="default")
     comfyui_url: str = Field(default="http://127.0.0.1:8188", description="ComfyUI Server URL")
     runninghub_api_key: str = Field(default="", description="RunningHub API Key (optional)")
     prompt_prefix: str = Field(