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/@smithy/util-base64/dist-es/constants.browser.js

@@ -0,0 +1,9 @@
+const chars = `ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/`;
+export const alphabetByEncoding = Object.entries(chars).reduce((acc, [i, c]) => {
+    acc[c] = Number(i);
+    return acc;
+}, {});
+export const alphabetByValue = chars.split("");
+export const bitsPerLetter = 6;
+export const bitsPerByte = 8;
+export const maxLetterValue = 0b111111;