[Feature] Code block supports displaying line numbers

[Ligayu]

Initial checklist

• I agree to follow the code of conduct
• I searched issues and discussions and couldn’t find anything (or linked relevant results below)

Problem

I want every line of the code block to be wrapped in a class.
like:

Then I can simply add css and display the line number.
like：
code {
counter-reset: step;
counter-increment: step 0;
}

  code .line::before {
    content: counter(step);
    counter-increment: step;
    width: 1rem;
    margin-right: 1.5rem;
    display: inline-block;
    text-align: right;
    color: rgba(115,138,148,.4)
  }

Solution

none

Alternatives

none