Wake runs stamp sourceSenderType into their secret scope, and the claim
query orders interactive-first: a wake born from an employee or board
message means a person is waiting at the keyboard, so it outranks any
autonomous backlog; within each lane FIFO holds. Non-chat runs carry no
stamp and stay in the autonomous lane. With wake expiry this closes the
live incident: the founder's CEO DM now claims on the next tick instead
of 13th in line. Red-green tested.
