Fork every briq of a stack into a new stack

Reach the fork from outside briq: database ports get TLS endpoints, front doors a URL in this mode ("private": only whoever has it). Outputs then use them. Waits for the forks

When the briq goes to sleep: after this long without use (agent calls, visits to its stack's URLs). A string: "30m", "3h", "7d" or "never", never a number. A sleeping briq keeps its disk, costs nothing for compute, and the next use wakes it. "never" keeps it always on (Pro plan and above). Left out, the source's. A window longer than this key allows is refused