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/lib/isBase64.js

@@ -0,0 +1,32 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = isBase64;
+var _assertString = _interopRequireDefault(require("./util/assertString"));
+var _merge = _interopRequireDefault(require("./util/merge"));
+function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
+var base64WithPadding = /^[A-Za-z0-9+/]+={0,2}$/;
+var base64WithoutPadding = /^[A-Za-z0-9+/]+$/;
+var base64UrlWithPadding = /^[A-Za-z0-9_-]+={0,2}$/;
+var base64UrlWithoutPadding = /^[A-Za-z0-9_-]+$/;
+function isBase64(str, options) {
+  var _options;
+  (0, _assertString.default)(str);
+  options = (0, _merge.default)(options, {
+    urlSafe: false,
+    padding: !((_options = options) !== null && _options !== void 0 && _options.urlSafe)
+  });
+  if (str === '') return true;
+  if (options.padding && str.length % 4 !== 0) return false;
+  var regex;
+  if (options.urlSafe) {
+    regex = options.padding ? base64UrlWithPadding : base64UrlWithoutPadding;
+  } else {
+    regex = options.padding ? base64WithPadding : base64WithoutPadding;
+  }
+  return (!options.padding || str.length % 4 === 0) && regex.test(str);
+}
+module.exports = exports.default;
+module.exports.default = exports.default;