Add raw() to point and tripoint.

[CLIDragon]

Summary

None

Purpose of change

This makes it possible to reason about a generic point object that may be a raw point / tripoint or a typed coordinate. This came up in #75961.

In particular, the change would allow expressing the following line:

const Point next = Point{ ( center + p).raw() };

for which there is currently no way to express. This would also allow getting rid of some overloads in favour of generic implementations (e.g. the closest_point_first overloads in coordinates.h)

Describe the solution

Add raw() methods to point and tripoint that create a new object with the same details.

Describe alternatives you've considered

Adding raw at callsites. This means that points have to be converted to the correct type system at the callsite, which is less than ideal.

Using template<typename Point, coords::origin Origin, coords::scale Scale>. However, I don't think this works with raw points, so they would have to be converted.

Testing

Additional context