Archive the bill

As the app's Archive. The bill drops out of default lists and totals (filter[archived] brings it back), isn't paid by vendor or recurring autopay, stops generating if it is a recurring template, isn't synced to accounting, and is read-only: other writes to it answer 409 until it is unarchived. A pending approval is cancelled. A bill whose payment is scheduled or processing can't be archived (422). Idempotent: archiving an archived bill returns it unchanged. Sends the bill.deleted webhook. Needs the role's Bills Archive permission, and bill archiving turned on for the account.