Deprecate implicit conversion between signed and unsigned integers

[Walter Bright]

On 2/7/2025 4:50 AM, Atila Neves wrote:
> I hate ugly code too, but I'd rather have explicit casts.

Pascal required explicit casts. It sounded like a good idea. After a while, I 
hated it. It was so nice switching to C and leaving that behind.

(Did I mention that explicit casts also hide errors introduced by refactoring?)