Read http-proxy from --http-proxy flag or build-livefs.conf and pass it
to the VM at launch time via cloud-init user-data (apt.http_proxy /
apt.https_proxy). Also set package_update: true so cloud-init runs
apt-get update on first boot, removing the need for an explicit call.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Creates (or reuses) a per-suite LXD VM, mounts the livecd-rootfs
checkout into it, waits for the VM to be ready, installs dependencies,
and runs build-livefs inside the VM — keeping the host clean.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>