feat(admin): 添加 S3 备份列表查看、下载和删除功能

- 在数据管理页面添加“查看备份”按钮，用于打开备份列表弹窗
- 新增 S3BackupModal 组件，展示备份文件列表，支持下载和删除操作
- 扩展 S3 工具类，支持列出、获取和删除 S3 对象
- 新增后端 API 接口：获取备份列表、删除备份、下载备份文件
- 为所有支持的语言添加相应的国际化文本

cwd-admin/src/locales/en-US.json

@@ -130,7 +130,15 @@
         "saving": "Saving...",
         "backup": "Backup to S3 Now",
         "backingUp": "Backing up...",
-        "success": "Backup successful! File: {file}"
+        "success": "Backup successful! File: {file}",
+        "viewBackups": "View Backups",
+        "loadingBackups": "Loading...",
+        "backupListTitle": "S3 Backup List",
+        "emptyBackupList": "No backup files",
+        "download": "Download",
+        "delete": "Delete",
+        "confirmDelete": "Are you sure you want to delete backup {file}?",
+        "deleteSuccess": "Deleted successfully"
       }
     },
     "logs": {