ci: check public headers conform to c++ ISO standards #4146

Job	Run time
Compile sysdeps (dripos)	2m 28s
Build mlibc (x86_64, mlibc, gcc)	1s
Compile sysdeps (lemon)	2m 27s
Build mlibc (x86_64, mlibc-static, gcc)	1s
Compile sysdeps (aero)	2m 30s
Build mlibc (x86_64, mlibc-shared, gcc)	1s
Build mlibc (x86_64, mlibc-ansi-only, gcc)	1s
Compile sysdeps (ironclad)	2m 39s
Build mlibc (x86_64, mlibc-headers-only, gcc)	1s
Compile sysdeps (lyre)	2m 25s
Build mlibc (riscv64, mlibc, gcc)	1s
Compile sysdeps (keyronex)	2m 40s
Build mlibc (riscv64, mlibc-static, gcc)	1s
Compile sysdeps (managarm)	2m 56s
Build mlibc (riscv64, mlibc-shared, gcc)	1s
Compile sysdeps (vinix)	2m 25s
Build mlibc (riscv64, mlibc-ansi-only, gcc)	1s
Compile sysdeps (astral)	2m 30s
Build mlibc (riscv64, mlibc-headers-only, gcc)	1s
Build mlibc (aarch64, mlibc, gcc)	2m 10s
Build mlibc (aarch64, mlibc-static, gcc)	2m 7s
Build mlibc (aarch64, mlibc-shared, gcc)	2m 10s
Build mlibc (aarch64, mlibc-ansi-only, gcc)	2m 9s
Build mlibc (aarch64, mlibc-headers-only, gcc)	2m 2s
Build mlibc (x86, mlibc, gcc)	1s
Build mlibc (x86, mlibc-static, gcc)	1s
Build mlibc (x86, mlibc-shared, gcc)	1s
Build mlibc (x86, mlibc-ansi-only, gcc)	1s
Build mlibc (x86, mlibc-headers-only, gcc)	1s
Build mlibc (m68k, mlibc, gcc)	2m 9s
Build mlibc (m68k, mlibc-static, gcc)	1s
Build mlibc (m68k, mlibc-shared, gcc)	2m 0s
Build mlibc (m68k, mlibc-ansi-only, gcc)	2m 3s
Build mlibc (m68k, mlibc-headers-only, gcc)	1m 59s
Build mlibc (x86_64, mlibc, clang)	1s
	42m 6s

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