Upload a bank or card file into the account's Bank Feeds card

The account needs a Bank Feeds card (connected to a bank, files only, or both) that is not hidden. Any dates are allowed. Rows an earlier upload already added (same date, amount, and cleaned description) are skipped by count; new rows that look like an existing bank or file row (same amount, dates within 3 days) are added and paired as possible duplicates. Added rows get rules, the AI pass, auto-post, and posting exactly like bank rows. Preview first; it writes nothing. When the date or amount column can't be found, the preview returns needsColumns with the headers, sample rows, and a suggested mapping; send the confirmed mapping with preview and commit. The mapping is remembered for the account.