[FR] Diff variant for code block

### Description

Hi, I''ve recently started to use AppFlowy, I use it as some sort of notes for learning, usually technical stuff.
That brings me to the question, how to create a diff text/codeblock.
With formatting, like in git, where lines with "+" sign at the beginning of the line have green color. and with "-" - red.

Example.

Is there any way to do that? Will it be implemented as separate codeblock language mode?

### Impact

People who do coding notes like programmers, admins, devops, etc.

### Additional Context

_No response_