refactor(storage): 将 storage 工具类导出名重命名为 storageUtil

- 将 utils/chromeStorage.ts 中的 storage 导出重命名为 storageUtil
- 更新 RoutePersistence.tsx 中的导入和引用以使用新名称
- 优化 recordUtils.tsx 中 chrome.downloads 的链式调用格式

使工具类的命名更加清晰，避免与全局 storage 概念混淆

components/RoutePersistence.tsx

@@ -1,6 +1,6 @@
 import { useEffect, useRef } from 'react';
 import { useLocation, useNavigate } from 'react-router-dom';
-import { storage } from '@/utils/chromeStorage';
+import { storageUtil } from '@/utils/chromeStorage';
 
 const RoutePersistence = () => {
   const location = useLocation();
@@ -13,7 +13,7 @@ const RoutePersistence = () => {
       if (isRestored.current) return;
 
       try {
-        const lastRoute = await storage.get('app/lastRoute');
+        const lastRoute = await storageUtil.get('app/lastRoute');
 
         if (lastRoute && lastRoute !== '/' && location.pathname === '/') {
           navigate(lastRoute, { replace: true });
@@ -32,7 +32,7 @@ const RoutePersistence = () => {
   useEffect(() => {
     const saveRoute = async () => {
       if (!isRestored.current) return;
-      await storage.set('app/lastRoute', location.pathname);
+      await storageUtil.set('app/lastRoute', location.pathname);
       console.log('保存路由', location.pathname);
     };