Adds web/deploy/install.sh — full LXC setup in one command. It derives the
repo path from its own location (clone anywhere; /opt/ponfw recommended),
installs git/node/npm if missing (checks Node >= 18), creates the ponfw
service user, runs npm install --omit=dev, writes /etc/pon-fleet-web.env on
first run, and installs+enables the systemd unit with WorkingDirectory set to
the checkout. Idempotent; warns if cloned under /home (ProtectHome blocks it).
README + CLAUDE.md §16 updated to lead with install.sh and clarify the clone
location.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
