bugfix: inputs/input.Makefile: %/VegBIEN.csv: for new-style datasources, use a symlink to mappings/VegCore-VegBIEN.csv directly instead of prefiltering VegCore-VegBIEN.csv to include only the columns in map.csv. prefiltering used to be performed as part of mapping the map.csv VegCore output terms to VegBIEN using bin/join, but is no longer needed because the staging table columns are now VegCore terms. instead, the full VegCore-VegBIEN.csv is needed so that derived columns added in stage I or II validations are detected by bin/map (rather than just the original source columns in map.csv).