The plan doc records what was measured and why each decision fell where it
did: the private bridge is worse than unhardened (a live NAT bridge with
IPv6 on), incus-user blocks snapshots, no daemon-level template exists (read
in incus-user's source), widening survives re-sync (same source, then
measured live). box-design gains the access-tiers section — including why
narrowing to boxnet-only is the load-bearing decision and why the nft bridge
drop is the layer a restricted user cannot strip. RUNS.md logs MU-1..3.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
