GdeltForge 0.6.1

Fixed

• filter silently wrote nothing whenever columns_to_check was empty, exactly the bundled default config's own value for every dataset. filter_single_file treated an empty columns_to_check the same as "columns were configured but none exist in this file's schema", logging an error and returning before ever writing the output file, while the batch summary still reported every file processed successfully with 100% retention. sample and crossref then correctly found nothing in the (empty) output directory, surfacing as confusing downstream errors with no indication the real failure was upstream and silent. The early-return now only fires when columns_to_check is actually non-empty; an empty list falls through to the existing, already-correct no-op path (dropna(subset=[]) is a documented pandas no-op)
• crossref --events crashed with a confusing ArrowInvalid: ... magic bytes not found error when pointed at a directory instead of a single file, if that directory contained a convert/filter .done resumability marker (<name>.parquet.done, a real sibling of the data by design in every one of their output directories). pd.read_parquet was handing the raw path straight to pandas with no awareness of that convention. --events now accepts a directory properly: every *.parquet file in it is read and concatenated, .done markers and any other non-parquet sibling are never handed to the parquet reader