Adds a parse → DB write → SFTP upload pipeline that closes the gap
where 837P submissions leave no DB row, making every 999 ack an
orphan. Locks the four brainstorming decisions (canonical submit flow,
DB-first ordering, new Batch.transaction_set_control_number column,
additive deprecation posture) and the architecture for one new CLI +
one new HTTP endpoint sharing a cyclone.submission helper.
Nora