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/isarray/test.js

@@ -0,0 +1,20 @@
+var isArray = require('./');
+var test = require('tape');
+
+test('is array', function(t){
+  t.ok(isArray([]));
+  t.notOk(isArray({}));
+  t.notOk(isArray(null));
+  t.notOk(isArray(false));
+
+  var obj = {};
+  obj[0] = true;
+  t.notOk(isArray(obj));
+
+  var arr = [];
+  arr.foo = 'bar';
+  t.ok(isArray(arr));
+
+  t.end();
+});
+