后端开发完成

backend/app/schemas/project_history.py

@@ -0,0 +1,17 @@
+from pydantic import BaseModel
+from datetime import datetime
+
+
+class ProjectHistoryResponse(BaseModel):
+    """项目历史记录响应模型"""
+    id: int
+    project_id: int
+    changed_by: int
+    change_field: str
+    old_value: str
+    new_value: str
+    change_description: str
+    created_at: datetime
+    
+    class Config:
+        from_attributes = True