[Feature]How to display the code block of the folded content in markdown format when using the <details> tag

[penghuima]

When I use the fold function

<details>
  <summary>折叠代码块</summary>
  ```bash
  echo "hello shell"
  echo "hello python"
  ```
</details>

折叠代码块

```bash echo "hello shell" echo "hello python" ```

the display result format is different from what I wanted

The ideal result I want is like as follows

And in the process of use, there should be no spaces. If there are spaces, the result is as follows

<details>
  <summary>折叠代码块</summary>
  ```bash
  echo "hello shell"

  echo "hello python"
  ```
</details>

Display error

[abnerlee]

put into #1939