Use `std::` prefix and mpu's EXPECTS_DEBUG macro #14

Job	Run time
std::format none C++20 Clang-18 Release	10m 1s
std::format none C++20 Clang-18 Debug	9m 14s
std::format none C++23 Clang-18 Release	9m 36s
std::format none C++23 Clang-18 Debug	8m 59s
std::format gsl-lite C++20 Clang-18 Release	10m 7s
std::format gsl-lite C++20 Clang-18 Debug	9m 11s
std::format gsl-lite C++23 Clang-18 Release	9m 27s
std::format gsl-lite C++23 Clang-18 Debug	9m 8s
std::format ms-gsl C++20 Clang-18 Release	10m 25s
std::format ms-gsl C++20 Clang-18 Debug	9m 22s
std::format ms-gsl C++23 Clang-18 Release	9m 26s
std::format ms-gsl C++23 Clang-18 Debug	9m 14s
fmtlib none C++20 Clang-18 Release	11m 16s
fmtlib none C++20 Clang-18 Debug	9m 25s
fmtlib none C++23 Clang-18 Release	10m 56s
fmtlib none C++23 Clang-18 Debug	9m 10s
fmtlib gsl-lite C++20 Clang-18 Release	9m 54s
fmtlib gsl-lite C++20 Clang-18 Debug	9m 42s
fmtlib gsl-lite C++23 Clang-18 Release	9m 23s
fmtlib gsl-lite C++23 Clang-18 Debug	9m 13s
fmtlib ms-gsl C++20 Clang-18 Release	9m 53s
fmtlib ms-gsl C++20 Clang-18 Debug	10m 50s
fmtlib ms-gsl C++23 Clang-18 Release	9m 38s
fmtlib ms-gsl C++23 Clang-18 Debug	12m 1s
	3h 55m 31s

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