Quarto and Rmarkdown are markdown variants popular with data scientists.

Lychee currently parses .qmd (Quarto) and .Rmd (RMarkdown) files with the plaintext parser, which leads to some surprising link checking failures if one converts a file from .md to .qmd, such as:

sample.qmd:

---
title: Sample
---

Real link: <https://example.com>.

```{.bash}
curl -O https://cdn.posit.co/r/rhel-10/pkgs/R-${R_VERSION}-1-1.$(arch).rpm
```

$ lychee --dump --verbose sample.qmd
https://example.com/ (sample.qmd) [excluded]
https://cdn.posit.co/r/rhel-10/pkgs/R-$%7BR_VERSION%7D-1-1.$(arch).rpm (sample.qmd)

Would you be open to a PR adding .qmd and .Rmd to the list of markdown extensions?

Thanks for considering, and for all of your work.