The branch inherits the data, not the wall

The PHI lab container runs in block mode. Nothing dials out, and the analysts like it that way. On Tuesday one of them wants to try a new feature-extraction library without touching the lab, so she branches it: POST /api/v1/containers/{lab}/copy with source_snapshot: "lab-2026-09-01".

The copy is up in a minute with every row, every notebook, every installed package. It is not up blocked. Firewall and network rules are not copied by default; the clone starts with a fresh network configuration, which means direct egress. To carry the wall across, the request has to say so: copy_network_rules: true, copy_firewall_rules: true.

That default is right for most branches and wrong for this one, so the lab's branch script sets both flags and nobody has to remember. The snapshot carried the dataset. Two booleans carried the isolation.