[clang-tidy] bugprone-implicit-widening ignores const exprs that fit (#98352)

Add an option to the
`bugprone-implicit-widening-of-multiplication-result` clang-tidy checker
to suppress warnings when the expression is made up of all compile-time
constants (literals, `constexpr` values or results, etc.) and the result
of the multiplication is guaranteed to fit in both the source and
destination types.

This currently only works for signed integer types:

* For unsigned integers, the well-defined rollover behavior on overflow
prevents the checker from detecting that the expression does not
actually fit in the source expr type, and would produce false negatives.
I have a somewhat-hacky stab at addressing this I'd like to submit as a
follow-on PR
* For floating-point types, there's probably a little additional work to
be done to `Expr` to calculate the result at compile time

Even still, this seems like a helpful addition just for signed types,
and additional types can be added.

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