VERSION holds MAJOR.MINOR (1.1), edited by hand. Every push to main is
tagged vMAJOR.MINOR.PATCH by the "Tag release" workflow, with PATCH counted
as an integer by scripts/next-version.sh. "Promote release" moves the major
tag (v1) to a tested release and refuses to move it backwards.
drb-update.sh: a newer release on the node's channel is now a reason to
update by itself. REF=latest follows the highest vX.Y.Z tag (test nodes);
REF=v1 follows the promoted tag (customer nodes). Versions compare per
field as integers (1.10.0 > 1.9.3, never string or float order). It never
downgrades, and an untagged target still needs a request. After an update
it writes DRB_VERSION to .env; the edge node reports it in checkin.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
