Map FEBR layer-table columns to soilKey horizon attributes
Source:R/febr.R
dot-FEBR_TO_HORIZON_MAP.RdThe FEBR camada (layer) table uses standardised variable
codes documented in the FEBR data dictionary (see
https://www.pedometria.org/febr/ for the project home;
the dictionary path moved during 2024 – the codes themselves
are stable). This internal table records the regex patterns that
map the most useful FEBR codes onto the soilKey horizon schema.
Multi-method codes (e.g.\ clay determined by hydrometer vs
sieve) are collapsed onto the single soilKey column.