Self-contained FAILED-relaunch scanner for chromebox-watchdog.log
with watermark at NETVM_ROOT/watchdog-alert-watermark.txt.
Exits 0 quiet when clean, 1 with new lines printed when alerting.
The box-ctl.py watchdog-alerts action (in 2db0d92) drives this script.
Session: sidechat/chromebox-ops
operator