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/isMagnetURI.js

@@ -0,0 +1,9 @@
+import assertString from './util/assertString';
+var magnetURIComponent = /(?:^magnet:\?|[^?&]&)xt(?:\.1)?=urn:(?:(?:aich|bitprint|btih|ed2k|ed2khash|kzhash|md5|sha1|tree:tiger):[a-z0-9]{32}(?:[a-z0-9]{8})?|btmh:1220[a-z0-9]{64})(?:$|&)/i;
+export default function isMagnetURI(url) {
+  assertString(url);
+  if (url.indexOf('magnet:?') !== 0) {
+    return false;
+  }
+  return magnetURIComponent.test(url);
+}