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/student.vue

@@ -0,0 +1,55 @@
+<template>
+    <div class="common-layout">
+        <el-container>
+            <el-header>
+                <Header></Header>
+            </el-header>
+
+            <el-main class="p-4">
+                <div class="bg-white dark:bg-gray-800 rounded-lg shadow p-6" v-loading="loading">
+                    <div class="text-lg font-semibold mb-4">学生详情</div>
+                    <template v-if="detail">
+                        <el-descriptions :column="1" border>
+                            <el-descriptions-item label="ID">{{ detail.id }}</el-descriptions-item>
+                            <el-descriptions-item label="姓名">{{ detail.name }}</el-descriptions-item>
+                            <el-descriptions-item label="班级">{{ detail.className }}</el-descriptions-item>
+                            <el-descriptions-item label="年级">{{ detail.gradeName }}</el-descriptions-item>
+                        </el-descriptions>
+                    </template>
+                    <template v-else>
+                        <el-empty description="暂无数据" />
+                    </template>
+                </div>
+            </el-main>
+
+        </el-container>
+    </div>
+</template>
+
+<script setup>
+import Header from '@/layouts/components/Header.vue'
+import { ref, onMounted } from 'vue'
+import { useRoute } from 'vue-router'
+import { getStudentDetail } from '@/api/student'
+
+const loading = ref(false)
+const detail = ref(null)
+const route = useRoute()
+
+async function fetchDetail() {
+    const id = route.params.id
+    if (!id) return
+    loading.value = true
+    try {
+        const res = await getStudentDetail(id)
+        const d = res.data
+        detail.value = d?.data || null
+    } finally {
+        loading.value = false
+    }
+}
+
+onMounted(() => {
+    fetchDetail()
+})
+</script>