Propose a clearing file's settlement reconciliation to the master account movement

Verified staff on the card clearing desk's narrow scopes only: cards:clearing:read for reads, cards:clearing:write with a step-up within five minutes for writes; cards:write does not reach these routes and no service token or API key does. The file formats are bank-defined approximations of the proprietary Visa BASE II, Mastercard IPM and Discover clearing specifications (services/cards/clearing/README.md); a file from the card clearing simulator is simulated, not network traffic. Proposes a processed file's settlement reconciliation against the evidenced master account movement (reference, lowercase SHA-256 of the retained advice, nonfuture value date, signed amount, positive when the network paid the bank). Every record is categorised (principal, credit, suspense debit or credit, return credit or debit, fee); posted presentments settle in principal batches of at most 250 with their interchange and scheme fees through network finance, and one direct journal carries credits (2310), suspense (2320), matched returns and unattributable interchange (4120) and fees (5500). The categories must add up to the trailer's net settlement and that net must equal the master account movement, or the proposal is 409 conflict. The file settles after its processing date's settlement date is reached, once, and a return credit settles only after the returned exception's own file settled.