Implement a new topology-based copy and paste solution for UVs.
Usage notes:
* Open the UV Editor
* Use the selection tools to select a Quad joined to a Triangle joined to another Quad.
* From the menu, choose UV > UV Copy
* The UV co-ordinates for your quad<=>tri<=>quad are now stored internally
* Use the selection tools to select a different Quad joined to a Triangle joined to a Quad.
* (Optional) From the menu, choose UV > Split > Selection
* From the menu, choose UV > UV Paste
* The UV co-ordinates for the new selection will be moved to match the stored UVs.
Repeat selection / UV Paste steps as many times as desired.
For performance considerations, see https://en.wikipedia.org/wiki/Graph_isomorphism_problem
In theory, UV Copy and Paste should work with all UV selection modes.
Please report any problems.
A copy has been made of the Graph Isomorphism code from https://github.com/stefanoquer/graphISO
Copyright (c) 2019 Stefano Quer stefano.quer@polito.it GPL v3 or later.
Additional integration code Copyright (c) 2022 by Blender Foundation, GPL v2 or later.
Maniphest Tasks: T77911
Differential Revision: https://developer.blender.org/D16278