Hans Goudey
cccf91ff83
As part of #95966, move the `ME_SEAM` flag on mesh edges to a generic boolean attribute, called `.uv_seam`. This is the last bit of extra information stored in mesh edges. After this is committed we can switch to a different type for them and have a 1/3 improvement in memory consumption. It is also now possible to see that a mesh has no UV seams in constant time, and like other similar refactors, interacting with only the UV seams can be done with less memory. The attribute name starts with a `.` to signify that the attribute, like face sets, isn't meant to be used in arbitrary procedural situations (with geometry nodes for example). That gives us more freedom to change things in the future. Pull Request #104728