Some mods appear to modify vertex formats to contain multiple attributes with the same semantic element (see #2218). While there is a potential way to make our implementation compatible, it adds complexity and likely makes things slower. Given that the overhead of the VertexConsumer interface is critical, and that mods doing this are very rare, we should instead opt to just not apply the optimizations if weirdness is encountered.

This can be achieved by changing the VertexConsumerProvider to return a specialized VertexConsumer with our optimized intrinsics, when the vertex format does not contain multiple attributes with the same semantic element.

Resolved with 1cc23f1.