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

utils/chromeStorage.ts

@@ -40,4 +40,4 @@ class StorageUtils {
   }
 }
 
-export const storage = new StorageUtils();
+export const storageUtil = new StorageUtils();

utils/recordUtils.tsx

@@ -55,11 +55,13 @@ export const downloadHtmlInBackground = (events: unknown[]) => {
   const blob = new Blob([htmlContent], { type: 'text/html' });
   const reader = new FileReader();
   reader.onload = () => {
-    chrome.downloads.download({
-      url: reader.result as string,
-      filename: `replay-${Date.now()}.html`,
-      saveAs: true,
-    }).then(r => console.log(r));
+    chrome.downloads
+      .download({
+        url: reader.result as string,
+        filename: `replay-${Date.now()}.html`,
+        saveAs: true,
+      })
+      .then((r) => console.log(r));
   };
   reader.readAsDataURL(blob);
 };