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-crypto/util/README.md

@@ -0,0 +1,16 @@
+# @aws-crypto/util
+
+Helper functions
+
+## Usage
+
+```
+import { convertToBuffer } from '@aws-crypto/util';
+
+const data = "asdf";
+const utf8EncodedUint8Array = convertToBuffer(data);
+```
+
+## Test
+
+`npm test`