Investigate whether it is still necessary to duplicate column data with different names in the categories of resulting SpatRaster objects

Previously this was done for compatibility with rasterVis which required a column actually called "ID" in the table (raster/early terra package holdover)

I think it is possible that with the latest versions of terra/rasterVis/etc. a single column (named anything, probably "mukey" for use with joins) will be sufficient