Deprecate `!a == b`

[IchorDev]

On Friday, 16 August 2024 at 19:23:19 UTC, Jonathan M Davis wrote:
> It wouldn't affect code that I would write, and if it fixed the 
> occasional bug, then that's arguably a good thing. However, I 
> definitely would rather not see this become an error for bool.
>
> - Jonathan M Davis

Problem is that a lot of C libraries use `alias LibSpecificBool = 
int;`. Maybe we just need a nice way to make C programmers less 
stu—I mean—to give integer type aliases bool semantics: `alias 
@boolean LibSpecificBool = int;`