feat: 添加图片生成功能及相关配置

- 添加图片生成相关配置和环境变量
- 新增图片上传服务和模型定义
- 扩展模型服务以支持图片生成模型
- 添加图片生成响应处理器
- 更新README文档以反映新功能
- 添加GitHub Actions发布工作流

app/services/model_service.py

@@ -2,10 +2,10 @@ import requests
 from datetime import datetime, timezone
 from typing import Optional, Dict, Any
 from app.core.logger import get_model_logger
+from app.core.config import settings
 
 logger = get_model_logger()
 
-
 class ModelService:
     def __init__(self, model_search: list):
         self.model_search = model_search
@@ -52,6 +52,11 @@ class ModelService:
                 "parent": None,
             }
             openai_format["data"].append(openai_model)
+            
+            if settings.CREATE_IMAGE_MODEL:
+                image_model = openai_model.copy()
+                image_model["id"] = f"{settings.CREATE_IMAGE_MODEL}-chat"
+                openai_format["data"].append(image_model)
 
             if model_id in self.model_search:
                 search_model = openai_model.copy()