audit_transform         Audit a sequence of geographic transformations
clean_geo_headers       Normalize messy geography headers to standard
                        names
prep_hud_crosswalk      Prepare HUD ZIP-to-County crosswalk
step_zcta_to_zip_equal
                        Step: ZCTA -> ZIP using equal-share allocation
step_zip_to_county_totratio
                        Step: ZIP -> COUNTY using HUD TOT_RATIO
