swarm-bao-nats-tls-policy acts with the bootstrap token, and main's
module-eval-bao-grants now fails any such unit whose calls the policy
file does not grant. Adds its three paths and counts it among the units
the check must see.
setup.md's copy of the swarm-bootstrap policy still granted only the
controller's first six paths, while eight units now act with the
bootstrap token. The policy moves to
nix/host-modules/swarm-bao-bootstrap-policy.hcl, now covering every path
those units call. module-eval-bao-grants reads that file and fails
when a unit whose script uses the token calls a path the file does not
grant.
