fix(mistakes): 修复错题掌握状态不返回的问题

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/services/exam_report_service.py

@@ -309,6 +309,7 @@ class MistakeService:
             ExamMistake.question_type,
             ExamMistake.knowledge_point_id,
             KnowledgePoint.name.label("knowledge_point_name"),
+            ExamMistake.mastery_status,
             ExamMistake.created_at
         ).select_from(ExamMistake).join(
             Exam, ExamMistake.exam_id == Exam.id
@@ -339,6 +340,7 @@ class MistakeService:
                 "question_type": row.question_type,
                 "knowledge_point_id": row.knowledge_point_id,
                 "knowledge_point_name": row.knowledge_point_name,
+                "mastery_status": row.mastery_status,
                 "created_at": row.created_at
             })
         

frontend/src/views/analysis/mistakes.vue

@@ -583,7 +583,7 @@ const loadMistakes = async () => {
       id: item.id,
       type: item.question_type || 'single',
       difficulty: 'medium',  // 暂无此字段
-      masteryStatus: 'unmastered',  // 暂无此字段
+      masteryStatus: item.mastery_status || 'unmastered',
       title: item.question_content,
       yourAnswer: item.user_answer,
       correctAnswer: item.correct_answer,