feat(review): 新增复习内容滚动展示与交互 API

- 新增 /review/feed 端点，合并报告和残片数据按时间倒序返回
- 新增 /review/report/{id} 和 /review/fragment/{id} 端点
- 支持复习内容在首页滚动展示及点击查看详情

src/main/java/com/guo/learningprogresstracker/service/ReviewService.java

@@ -0,0 +1,29 @@
+package com.guo.learningprogresstracker.service;
+
+import com.guo.learningprogresstracker.dto.ReviewFeedItem;
+import com.guo.learningprogresstracker.entity.StudyReportFragmentsEntity;
+import com.guo.learningprogresstracker.entity.StudyReportsEntity;
+import com.guo.learningprogresstracker.exception.NotFindEntitiesException;
+
+import java.util.List;
+
+/**
+ * 复习模块 Service 接口
+ */
+public interface ReviewService {
+
+    /**
+     * 获取复习 feed 列表，合并报告和残片按时间倒序
+     */
+    List<ReviewFeedItem> getReviewFeed(int limit);
+
+    /**
+     * 获取报告详情
+     */
+    StudyReportsEntity getReportDetail(int id) throws NotFindEntitiesException;
+
+    /**
+     * 获取残片详情
+     */
+    StudyReportFragmentsEntity getFragmentDetail(int id) throws NotFindEntitiesException;
+}

src/main/java/com/guo/learningprogresstracker/service/impl/ReviewServiceImpl.java

@@ -0,0 +1,44 @@
+package com.guo.learningprogresstracker.service.impl;
+
+import com.guo.learningprogresstracker.dto.ReviewFeedItem;
+import com.guo.learningprogresstracker.entity.StudyReportFragmentsEntity;
+import com.guo.learningprogresstracker.entity.StudyReportsEntity;
+import com.guo.learningprogresstracker.exception.NotFindEntitiesException;
+import com.guo.learningprogresstracker.mapper.ReviewMapper;
+import com.guo.learningprogresstracker.mapper.StudyReportFragmentsMapper;
+import com.guo.learningprogresstracker.mapper.StudyReportsMapper;
+import com.guo.learningprogresstracker.service.ReviewService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * 复习模块 Service 实现
+ */
+@Service
+@RequiredArgsConstructor
+public class ReviewServiceImpl implements ReviewService {
+
+    private final ReviewMapper reviewMapper;
+    private final StudyReportsMapper studyReportsMapper;
+    private final StudyReportFragmentsMapper studyReportFragmentsMapper;
+
+    @Override
+    public List<ReviewFeedItem> getReviewFeed(int limit) {
+        return reviewMapper.selectReviewFeed(limit);
+    }
+
+    @Override
+    public StudyReportsEntity getReportDetail(int id) throws NotFindEntitiesException {
+        return Optional.ofNullable(studyReportsMapper.selectById(id))
+                .orElseThrow(() -> new NotFindEntitiesException("学习报告[" + id + "]不存在"));
+    }
+
+    @Override
+    public StudyReportFragmentsEntity getFragmentDetail(int id) throws NotFindEntitiesException {
+        return Optional.ofNullable(studyReportFragmentsMapper.selectById(id))
+                .orElseThrow(() -> new NotFindEntitiesException("学习残片[" + id + "]不存在"));
+    }
+}