新增虚拟滚动阈值逻辑以优化性能，改进可视化数据计算和滚动处理，确保在数据量较小时直接渲染全部数据。

src/App.vue

@@ -3,7 +3,7 @@ import ProjectList from './components/ProjectList.vue'
 import type { ListItem, MenuItem } from '@/types'
 
 // 生成模拟数据
-const listData: ListItem[] = Array.from({ length: 789 }, (_, i) => ({
+const listData: ListItem[] = Array.from({ length: 50 }, (_, i) => ({
   id: i,
   name: `project-${i + 1}`,
   path: `/Users/lanyuanxiaoyao/Project/IdeaProjects/project-${i + 1}`,