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/middleware-flexible-checksums/dist-es/hasHeader.js

@@ -0,0 +1,9 @@
+export const hasHeader = (header, headers) => {
+    const soughtHeader = header.toLowerCase();
+    for (const headerName of Object.keys(headers)) {
+        if (soughtHeader === headerName.toLowerCase()) {
+            return true;
+        }
+    }
+    return false;
+};