Workflow now publishes ISO as 1900M chunks. Test harness needs to:
1. gh release download --pattern '*.iso.part-*'
2. cat parts back into single ISO
3. verify sha256 of all parts
If invoked with no ISO arg, auto-fetches from ci-latest release.
Falls back to local ISO path if given as arg (existing behavior).
Reassembled ISO lives at ~/veilor-iso/ci-latest/.
test/auto-install.sh boots ISO, drives gum installer via QEMU
monitor sendkey with hardcoded test answers, waits for anaconda,
reboots into installed system, SSHs in, runs validation checklist.
Co-authored-by: veilor-org <admin@veilor.org>