Derive PartialEq, Serialize, Deserialize and Reflect on primitives

[NiseVoid]

Objective

• Implement common traits on primitives

Solution

• Derive PartialEq on types that were missing it.
• Derive Copy on small types that were missing it.
• Derive Serialize/Deserialize if the feature on bevy_math is enabled.
• Add a lot of cursed stuff to the bevy_reflect impls module.

[NiseVoid]

Deriving Serialize/Deserialize on the types with const generics isn't currently possible. But we could manually implement it with some extra code.
Reflect doesn't seem to work with Box<[T]>, we could skip the Boxed variants, manually implement reflect for Box<[T]>, or change the types to Vec<T>

[MrGVSV]

Nit: Could we maybe move these files into a new math module? That way we can group it with the rect and glam modules.

[NiseVoid]

Since they're sort of behind different features, I kept glam separate from math, but grouped all the bevy_math stuff together ... We could also change the features so glam is the same feature (tho that might be really annoying if anyone uses glam and bevy_reflect, but not bevy_math outside of bevy)

[NiseVoid]

I fixed the serialize thing on primitives with a fairly common workaround, but implementing Reflect for Box<[T]> seems a bit more complicated. If it's something we want that should probably be in a different PR later.

Also not quite sure why check-bans is failing 🤔

[alice-i-cecile]

LGTM once dead code is cleaned up. It's annoying that we can't just use the derive macro, but circular dependencies are real.