Nomad's docker task driver reports Healthy=false without a running
dockerd. On the factory dev box docker was pre-installed so Step 0's
cluster-up passed silently, but a fresh ubuntu:24.04 LXC hit "missing
drivers" placement failures the moment Step 1 tried to deploy forgejo
(the first docker-driver consumer).
Fix install.sh to also install docker.io + enable --now docker.service
when absent, and add a poll for the nomad self-node's docker driver
Detected+Healthy before declaring Step 8 done — otherwise the race
between dockerd startup and nomad driver fingerprinting lets the node
reach "ready" while docker is still unhealthy.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
