Filters transactions to those on or after the bank's configured start date.
Back-compat shim consumed by AccountImporter; phase-3 migrates it.
Transactions to filter; not mutated.
Bank config providing the cutoff date.
Filtered array, or original if no date filter is configured.
Filters transactions to those on or after the bank's configured start date.
Back-compat shim consumed by AccountImporter; phase-3 migrates it.