feat(web): tree batch auto-expand with depth limit and view icons

勾选文件树文件夹时自动展开并懒加载子节点，按最大深度（默认 4，勾选文件夹为第 0 层）递归收集可下载文件；触及上限时中文提示部分文件已跳过。树侧栏顶部增加显眼的批量下载入口。Home/ShowList 窗格与文件树切换增加 Font Awesome 图标。

Co-authored-by: qaiu <[email protected]>

web-front/package.json

@@ -7,7 +7,8 @@
     "dev": "vue-cli-service serve",
     "build": "node scripts/sync-version.js && vue-cli-service build && node scripts/compress-vs.js",
     "build:no-compress": "node scripts/sync-version.js && vue-cli-service build",
-    "lint": "vue-cli-service lint"
+    "lint": "vue-cli-service lint",
+    "test": "node --test src/utils/batchTreeCollect.spec.js"
   },
   "dependencies": {
     "@element-plus/icons-vue": "^2.3.1",