feat(student): 添加学生详情页及相关路由和跳转按钮

- 在 class.vue 中增加“详情”按钮，可跳转至对应学生详情页
- 使用 vue-router 的 useRouter 实现页面跳转功能
- 添加 /student/:id 路由，绑定学生详情组件 student.vue
- 新增 student.vue 组件，展示学生详细信息
- 精简 Header.vue, 移除多余导航链接，优化界面展示

enlish-vue/src/pages/class.vue

@@ -61,8 +61,9 @@
                             <el-table-column prop="name" label="姓名" min-width="120" />
                             <el-table-column prop="classId" label="班级ID" width="100" />
                             <el-table-column prop="gradeId" label="年级ID" width="100" />
-                            <el-table-column label="操作" width="120" fixed="right">
+                            <el-table-column label="操作" width="180" fixed="right">
                                 <template #default="{ row }">
+                                    <el-button type="primary" size="small" @click.stop="onViewStudent(row)">详情</el-button>
                                     <el-button type="danger" size="small" @click.stop="onDeleteStudent(row)">删除</el-button>
                                 </template>
                             </el-table-column>
@@ -167,6 +168,7 @@ import AddStudentDialog from '@/layouts/components/AddStudentDialog.vue'
 import LessonPlanDialog from '@/layouts/components/LessonPlanDialog.vue'
 import { getUnitList, deleteUnit } from '@/api/unit'
 import AddUnitDialog from '@/layouts/components/AddUnitDialog.vue'
+import { useRouter } from 'vue-router'
 
 const classes = ref([])
 const pageNo = ref(1)
@@ -207,6 +209,7 @@ const unitTotalCount = ref(0)
 const unitLoading = ref(false)
 const unitTableRef = ref(null)
 const showAddUnitDialog = ref(false)
+const router = useRouter()
 
 async function fetchClasses() {
     loading.value = true
@@ -289,6 +292,9 @@ function handleStudentSizeChange(s) {
 function onStudentSelectionChange(rows) {
     selectedStudentIds.value = rows.map(r => r.id)
 }
+function onViewStudent(row) {
+    router.push(`/student/${row.id}`)
+}
 function onClassRowClick(row) {
     selectedClassId.value = row.id
     selectedClassTitle.value = row.title