循环节点出参不能选择数组和字典类型

**Describe the bug**

循环节点出参不能选择数组和字典类型

**To Reproduce**

Steps to reproduce the behavior:
1. 工作流添加循环节点
2. 循环节点出参选择数组类型或字典类型
3. 界面没有变化，跳回字符串类型
4. 最终表现是无法引用到数组或字典类型的输出变量

**Expected behavior**

无法引用循环体中字典或数组类型的输出

**Screenshots**

Start by reproducing the issue in a workflow with a loop node, selecting array and dictionary output types. Trace the loop node's output-type selector and the referenceable output variables; done means both types remain selected and their outputs can be referenced instead of reverting to string.

Written by the indexing model from the issue text.