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/stripLow.js

@@ -0,0 +1,7 @@
+import assertString from './util/assertString';
+import blacklist from './blacklist';
+export default function stripLow(str, keep_new_lines) {
+  assertString(str);
+  var chars = keep_new_lines ? '\\x00-\\x09\\x0B\\x0C\\x0E-\\x1F\\x7F' : '\\x00-\\x1F\\x7F';
+  return blacklist(str, chars);
+}