Better TeX highlighting

[thematdev]

Diff at line 280 is needed to display math mode not with default color. I'm really curious why does Special have the same color as text, but if you want you can make it filetype-specific.

I decided to use nord15 instead of nord13 for texSpecialChar because it doesn't look good to highlight all brackets in yellow color.

Preview:

[thematdev]

Just for comparison, how does it look without this patch

[svengreb]

Thank you for your patience! 🙏🏼
It‘s been a while since I had free time to focus more on Nord, and my open source projects in general, and invest time in this issue due to work-life balance.

I recently published the first “Northern Post — The state and roadmap of Nord“ announcement which includes all details about the plans and future of the Nord project, including the goal of catching up with the backlog. This issue is part of the backlog and therefore I want to triage and process it to get one step closer to a “clean state“. Read the announcement about reaching the “clean“ contribution triage state in Nord‘s discussions for more details about the goal.

Therefore it has been added for triage in the central and single-source-of-truth project board that is also described in more detail in the roadmap announcement.

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@thematdev Thanks for your contribution 🚀
The pull request has been added for triage and the review will be planned for the next iterations!