[Feature Request] add highlighting for .diff/.patch

Context

• This issue is not a bug report. (please use a different template for reporting a bug)
• This issue is not a duplicate of an existing issue. (please use the search to find existing issues)

Description

So far that isn't included in the samples, so I guess it isn't available as a "plain" highlighter (handling comment/hint lines, giving the background of + / - a green/red style.

I came here checking if this is supported in monaco-editor as the PowerToys preview doesn't handle it - but it seems to be really missing here (if not, then it is missing in the examples).

Monaco Editor Playground Link

No response

Monaco Editor Playground Code

No response