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/@aws-sdk/xml-builder/dist-es/XmlText.js

@@ -0,0 +1,10 @@
+import { escapeElement } from "./escape-element";
+export class XmlText {
+    value;
+    constructor(value) {
+        this.value = value;
+    }
+    toString() {
+        return escapeElement("" + this.value);
+    }
+}