fix: 数据看板使用趋势 Y 轴步进值调整为 1

- 修改 DashboardView.vue 中趋势图表的 Y 轴配置
- 左右 Y 轴（授课次数、学生数）的步进值均设为 1

reading-platform-frontend/src/views/admin/DashboardView.vue

@@ -35,7 +35,7 @@
         </div>
         <div class="stat-content">
           <span class="stat-value">{{ statsData.studentCount }}</span>
-          <span class="stat-label">覆盖学生</span>
+          <span class="stat-label">学生总数</span>
         </div>
       </div>
     </div>
@@ -82,9 +82,9 @@
               <div class="rank-number" :class="'rank-' + (index + 1)">{{ index + 1 }}</div>
               <div class="rank-content">
                 <span class="rank-name">{{ item.name }}</span>
-                <span class="rank-desc">活跃用户: {{ item.lessonCount }}</span>
+                <span class="rank-desc">活跃教师：{{ item.activeTeacherCount }} 人</span>
               </div>
-              <a-tag color="blue">{{ item.lessonCount }} 课程</a-tag>
+              <a-tag color="blue">{{ item.completedLessonCount }} 课次</a-tag>
             </div>
           </div>
           <a-empty v-else description="暂无数据" />
@@ -292,6 +292,7 @@ const initTrendChart = (data: TrendData[]) => {
         type: 'value',
         name: '授课次数',
         position: 'left',
+        interval: 1,
         splitLine: {
           lineStyle: {
             color: '#F3F4F6',
@@ -302,6 +303,7 @@ const initTrendChart = (data: TrendData[]) => {
         type: 'value',
         name: '学生数',
         position: 'right',
+        interval: 1,
         splitLine: {
           show: false,
         },

reading-platform-java/src/main/resources/db/migration/V10__update_course_package_stats.sql

@@ -1,37 +0,0 @@
--- -----------------------------------------------------
--- V10: 更新课程包统计数据
--- 说明：根据 lesson 表实际数据更新 course_package 的 usage_count 和 teacher_count
--- 时间：2026-03-20
--- -----------------------------------------------------
-
--- 1. 更新 usage_count：统计 status != 'cancelled' 的课程数
-UPDATE course_package cp
-SET usage_count = (
-    SELECT COUNT(*)
-    FROM lesson l
-    WHERE l.course_id = cp.id
-    AND l.status != 'cancelled'
-    AND l.deleted = 0
-)
-WHERE cp.deleted = 0;
-
--- 2. 更新 teacher_count：统计 status = 'completed' 的课程中去重教师数
-UPDATE course_package cp
-SET teacher_count = (
-    SELECT COUNT(DISTINCT l.teacher_id)
-    FROM lesson l
-    WHERE l.course_id = cp.id
-    AND l.status = 'completed'
-    AND l.teacher_id IS NOT NULL
-    AND l.deleted = 0
-)
-WHERE cp.deleted = 0;
-
--- 3. 处理 NULL 值，确保字段为 0 而不是 NULL
-UPDATE course_package cp
-SET usage_count = 0
-WHERE usage_count IS NULL AND deleted = 0;
-
-UPDATE course_package cp
-SET teacher_count = 0
-WHERE teacher_count IS NULL AND deleted = 0;