Avoid copying the positions array into the evaluated edit hints array
that's used to support editing with deformed positions when there is
a topology-changing procedural operation. In a simple test in sculpt
mode with 706k curve points, memory usage went from 78 to 70 MB.
This adds more duplication would be ideal, mainly because retrieving
the data with write access and making implicit sharing info for arbitrary
arrays aren't abstracted by implicit sharing utilities. It may be possible
to improve both of those aspects, either now or in the future.
Pull Request: https://projects.blender.org/blender/blender/pulls/120146
Similar to 2e6223d90f, but potentially 16 times more effective.
The new attribute is named "instance_transform". It isn't displayed in the
spreadsheet since that wouldn't really be useful. This simplifies a lot of
code since it doesn't have to handle transforms specially anymore. But
complexity is added in the store named attribute node and attribute input
node to keep the old "position" attribute working for compatibility.
Pull Request: https://projects.blender.org/blender/blender/pulls/118531
