UV Export: add option to export UV tiles
Tiles can now be exported, with either the UDIM or UVTILE numbering
scheme.
Exporters for PNG, SVG and EPS were updated. The vector formats simply
offset the view, so all UVs can end up being exported multiple times.
Only tiles containing UV points will be exported. In theory, this may
result in some polygons being ignored, if they cross a whole otherwise
empty tile, but this should not happen in practice.
Fixes #74325
Pull Request: https://projects.blender.org/blender/blender-addons/pulls/104940