Releases: VERSION + automatic patch tags + promote; updater installs newer versions (node-26#49)

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>

.gitea/workflows/promote.yml

@@ -0,0 +1,39 @@
+name: Promote release
+
+# node-26#49: move the major tag (v1) to a tested release. Customer nodes
+# (updater REF=v1) install it on their next timer run, because its version is
+# numerically higher than what they run. Never moves it backwards.
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: "Release to promote, e.g. 1.1.3 (must already be tagged v1.1.3)"
+        required: true
+
+jobs:
+  promote:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Move the major tag
+        env:
+          VERSION: ${{ inputs.version }}
+        run: |
+          [[ "$VERSION" =~ ^([0-9]+)\.[0-9]+\.[0-9]+$ ]] || { echo "version must be MAJOR.MINOR.PATCH, got '$VERSION'"; exit 1; }
+          MAJOR="${BASH_REMATCH[1]}"
+          git fetch --force --tags origin
+          git rev-parse -q --verify "refs/tags/v$VERSION" >/dev/null || { echo "tag v$VERSION does not exist"; exit 1; }
+          # Refuse to go backwards: compare with the release v$MAJOR points at now.
+          CUR="$(git tag --points-at "v$MAJOR" 2>/dev/null | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$' \
+                 | sed 's/^v//' | sort -t. -k1,1n -k2,2n -k3,3n | tail -1 || true)"
+          if [ -n "$CUR" ]; then
+            HIGHEST="$(printf '%s\n%s\n' "$CUR" "$VERSION" | sort -t. -k1,1n -k2,2n -k3,3n | tail -1)"
+            [ "$HIGHEST" = "$VERSION" ] || { echo "v$MAJOR is at $CUR, newer than $VERSION — refusing to roll back here"; exit 1; }
+          fi
+          git tag -f "v$MAJOR" "v$VERSION^{commit}"
+          git push --force origin "refs/tags/v$MAJOR"
+          echo "v$MAJOR -> $VERSION (was ${CUR:-untagged})"

.gitea/workflows/version-tag.yml

@@ -0,0 +1,31 @@
+name: Tag release
+
+# node-26#49: every push to main is a release, vMAJOR.MINOR.PATCH (see
+# scripts/next-version.sh). Test nodes (updater REF=latest) install the
+# highest tag on their next timer run; customer nodes (REF=v1) wait for the
+# Promote workflow.
+
+on:
+  push:
+    branches: [main]
+
+concurrency:
+  group: version-tag
+  cancel-in-progress: false
+
+jobs:
+  tag:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Tag this commit
+        run: |
+          git fetch --force --tags origin
+          TAG="$(bash scripts/next-version.sh)"
+          if [ -z "$TAG" ]; then echo "already tagged"; exit 0; fi
+          git tag "$TAG"
+          git push origin "refs/tags/$TAG"
+          echo "released $TAG"