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/dotenv/config.js

@@ -0,0 +1,9 @@
+(function () {
+  require('./lib/main').config(
+    Object.assign(
+      {},
+      require('./lib/env-options'),
+      require('./lib/cli-options')(process.argv)
+    )
+  )
+})()