Use Vec3A for 3D bounding volumes and raycasts

[NiseVoid]

Objective

• People have reported bounding volumes being slower than their existing solution because it doesn't use SIMD aligned types.

Solution

• Use Vec3A internally for bounding volumes, accepting Into<Vec3A> wherever possible
• Change some code to make it more likely SIMD operations are used.

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Changelog

• Use Vec3A for 3D bounding volumes and raycasts

Migration Guide

• 3D bounding volumes now use Vec3A types internally, return values from methods on them now return Vec3A instead of Vec3

[NthTensor]

Do we have a good test to best mark this on?

[IQuick143]

Seems like straightforward changes, I haven't spotted any problems.

[IQuick143]

is the signum needed here?

[NiseVoid]

Without the signum it'll break on 0 vs -0, signum always turns it into 1 or -1 ... Would be nice if glam had a function to get a BVec3A for the signs directly tho 🤔