A non-empty invalid transaction_date ('N/A') passed presence-only validation,
then new Date(str).toISOString() threw mid-import: nothing imported, no toast,
and setImporting(false) never ran, sticking the button on 'Importing...'.
Extracted parsePaymentRow to lib/import-logic.ts with a date guard, and wrapped
runImport so the importing flag always clears.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>