AK: Add optional `message` argument to VERIFY and friends

[stasoid]

This PR effectively reverts 079edff.

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This works only in clang-cl, doesn't work in clang/gcc by default:

#define VERIFY(expr, msg...) func(#expr, msg)

This works in 2 CIs, fails in other two with expected primary-expression before ‘)’ token:

#define VERIFY(expr, msg...) func(#expr ,##msg)

This produces warning: __VA_OPT__ can only appear in the expansion of a C++2a variadic macro:

#define VERIFY(expr, msg...) func(#expr __VA_OPT__(,) msg)

That's how I arrived at this abomination:

#define VERIFY(expr, ...) func(#expr __VA_OPT__(,) __VA_ARGS__)