agda highlight

Is this PR still active?
@weisi The PR is still in the backlog, but requires a more detailed review and revision since I'm not familiar with Agda and the screenshot shows some elements that need to be changed regarding the coloring. As soon as the data transition of all Nord port projects to the new shiny website is completed there is more time again to process all the open issues and PRs from all Nord repositories.
Can confirm that as of today, patching this block into nord-theme.el works just fine. Not an advanced user so can't speak to the ergonomics of some of the color choices, but it's certainly a huge improvement over the default colorings one gets in Agda mode using default nord.
For now I've forked 0.5 as nord-agda-theme.el with (deftheme nord-agda ...).
If I get the time (and after learning more Agda...) I'll try to figure out where the theme diverges from guidelines, make the edits, and hopefully we can get this into main.