Standardize and generalize out-of-tree transforms

[teh-cmc]

• We have in-tree transforms today: "mono" components that affect the transform of a given entity as well as all of its children
• We also need some way of specifying out-of-tree transforms: transforms that only apply to a single entity (or rather, a single instance of that entity), without affecting its chidren
  • E.g. logging an array of 3D boxes that have different orientations
  • E.g. scaling a mesh without affecting its children

The alternative is to add extra layers of empty nodes, which quickly gets less ergonomic, especially with batches.

[jleibs]

I believe we can consider this done as part of:

• Rename LeafTransforms3D to InstancePoses3D, disable implicit empty component logging for it #7143