Everywhere, normalize the whitespace to ::new (EXPR) T.
Everywhere, normalize the spelling of the cast to (void*)EXPR.
Without the cast to (void*), the expression triggers ADL on GCC.
(I think this is a GCC bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98249)
Even if it doesn't trigger ADL, it still seems incorrect to use any argument that's not exactly (void*) because that opens the possibility of overload resolution picking a user-defined overload of operator new, which would be wrong.
(I admit this is nitpicky and code-churny, but it's also cleanup. I'm particularly interested to see if buildkite will tell me exactly why __voidify was needed for the constexpr construct_at stuff; that's the one slightly scary change hiding in this PR.)