修复加减分失败但计入记录和添加导出功能

backend/services/conduct_service.py

@@ -80,6 +80,18 @@ class ConductService:
                     fail_count += 1
                     continue
                 
+                # 检查分数是否会超出范围（防止溢出）
+                current_points = student.get("total_points", 0)
+                new_points = current_points + points_change
+                if new_points < 0:
+                    details.append({"student_id": student_id, "error": f"分数不能为负（当前{current_points}，操作{points_change}）"})
+                    fail_count += 1
+                    continue
+                if new_points > 100:
+                    details.append({"student_id": student_id, "error": f"分数不能超过100（当前{current_points}，操作{points_change}）"})
+                    fail_count += 1
+                    continue
+                
                 # 创建记录
                 record_id = await ConductModel.create_record(
                     student_id=student_id,
@@ -102,7 +114,7 @@ class ConductService:
                 fail_count += 1
         
         return {
-            "success": True,
+            "success": fail_count == 0,
             "success_count": success_count,
             "fail_count": fail_count,
             "details": details