Now that clang-format makes [[nodiscard]] attributes format sensibly, we
can apply them to several functions within the common library to allow
the compiler to complain about any misuses of the functions.
Previously the constructor for all of these would run at program
startup, consuming time before the application can enter main().
This is also particularly dangerous, given the logging system wouldn't
have been initialized properly yet, yet the program would use the logs
to signify an error.
To rectify this, we can replace the literals with constexpr functions
that perform the conversion at compile-time, completely eliminating the
runtime cost of initializing these arrays.
Avoids potentially performing multiple reallocations (depending on the
size of the input data) by reserving the necessary amount of memory
ahead of time.
This is trivially doable, so there's no harm in it.
These can be generified together by using a concept type to designate
them. This also has the benefit of not making copies of potentially very
large arrays.
