refactor: use concepts even more

[scarf005]

Checklist

Required

• I wrote the PR title in conventional commit format.
• I ran the code formatter.
• I linked any relevant issues using github keyword syntax so it can be closed automatically.
• I have committed my changes to new branch that isn't main so it won't cause conflict when updating main branch later.

Purpose of change

followup to #5537: apply https://clang.llvm.org/extra/clang-tidy/checks/modernize/use-constraints.html

Describe the solution

ran:

$ parallel ./build-scripts/clang-tidy-wrapper.sh {} -fix '--checks=-\*,modernize-use-constraints,modernize-type-traits' ::: src/*.{cpp,h}

btw it took 370s lol

Testing

should (probably) build

[OrenAudeles]

a few build errors on this one still :(

[OrenAudeles]

This was a pretty big PR, but thankfully wasn't doing anything weird. It was easy to see why the changes were being made blah<T>::type to blah_t<T> and blah<T>::value to blah_v<T> mostly, along with changing over from enable_if to requires syntax

[chaosvolt]

It's a lot to go over but it compiles and loads, and only tests that're failing are clang whining about unrelated things again: https://github.com/cataclysmbnteam/Cataclysm-BN/actions/runs/11241032936/job/31251730123?pr=5538