Add interest color to envision.

[Gamenot]

#1967

[Gamenot]

This ended up being abnormally tricky.

• The first issue is that all the instanced meshes share the same material (which is good for performance reasons) but it meant that changing the diffuseColor would cause all instances to change colour. The solution was recommended to use a colour buffer.
• However, it seems like gltf files are loaded with some odd scaling that causes colour buffer values to not reflect on the mesh instances the template mesh is still parented to its original root node.

I honestly thought I was going crazy for a bit there because it looked like it should have worked.