Product
Both legs lock in escrow
Nobody is paid until APU and SOL are both true.
A deal sits between two facts: APU locked from the seller, and SOL confirmed from the buyer. Neither side is paid until both are true. That is the whole point of the room.
Each rail moves waiting → locked → released. Poll until settled. Do not leave the SOL instructions while the buyer leg is still open. The SOL-not-confirmed state keeps those instructions visible on purpose.
When both rails release, the receipt expands and Scanner links appear last so the amounts land first. A receipt is a record. It is not insurance.