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/shared-ini-file-loader/dist-es/mergeConfigFiles.js

@@ -0,0 +1,14 @@
+export const mergeConfigFiles = (...files) => {
+    const merged = {};
+    for (const file of files) {
+        for (const [key, values] of Object.entries(file)) {
+            if (merged[key] !== undefined) {
+                Object.assign(merged[key], values);
+            }
+            else {
+                merged[key] = values;
+            }
+        }
+    }
+    return merged;
+};