Add Wedge to primitive shapes

[lynn-lumen]

What problem does this solve or what need does it fill?

The RFC mentions a few primitive shapes like Wedge or Cone that are not included in bevy_math::primitives or that do not implement bevy_render::mesh::Meshable and cannot be used as shapes for Meshes.

• Cone is implemented in bevy_math and can be used as a gizmo but not as a Mesh primitive.
• Wedge is not implemented anywhere.

What solution would you like?

Add Wedge to bevy_math and implement Meshable for both.

What alternative(s) have you considered?

Implement Meshable for Cone and don't add Wedge at all.

Additional context

I think Ramp would be a better name for the Wedge shape as described in the RFC mentioned above because not every wedge is a ramp and not every ramp is a wedge.

For example in this image:

• The left shape is a valid ramp, but not a wedge (This shape conforms to what is described in the RFC)
• The right shape is a valid wedge but not a ramp.