fix: 修复配额说明重复和undefined问题

- 在editStorageForm中初始化oss_storage_quota_value和oss_quota_unit
- 删除重复的旧配额说明块，保留新的当前配额设置显示

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/node_modules/validator/es/lib/isMultibyte.js

@@ -0,0 +1,10 @@
+import assertString from './util/assertString';
+
+/* eslint-disable no-control-regex */
+var multibyte = /[^\x00-\x7F]/;
+/* eslint-enable no-control-regex */
+
+export default function isMultibyte(str) {
+  assertString(str);
+  return multibyte.test(str);
+}