Use treesitter highlighting in code blocks

[GuillaumeLagrange]

Issue Description

Type: feature request

Describe what happened (or what feature you want)

Code blocks are not very readable in comments/pr descriptions

Describe what you expected to happen

The native markdown parser supports syntax highlighting inside code blocks, we may be able to configure something to support this!

Tell us your environment

NVIM v0.10.1
Build type: Release
LuaJIT 2.1.1713773202
Run "nvim -V1 -v" for more info

Anything else we need to know?

I have not yet deepdived into my ts config, but I believe default ops ought to do this in recent versions of nvim, let me know if there are reproducibility issues