This struct is currently defined in the `functions` module but not actually used there. It's only used by the geometry nodes module, with an indirect dependency from blenkernel via simulation zone baking. This scope is problematic when adding grids as socket data, which should not be part of the functions module.
The `ValueOrField` struct is now moved to blenkernel, so it can be more easily extended to other kinds of data that might be passed around by geometry nodes sockets in future. No functional changes.
Pull Request: https://projects.blender.org/blender/blender/pulls/115087
c845233d1c