ci: derive release notes from CHANGELOG.md + support version tags

- Extract the relevant CHANGELOG.md section as the release body instead of the
  static "Auto-built from SHA": on a vX.Y tag take that version's section, else
  the latest released version section.
- Publish step is now tag-aware: a vX.Y tag push builds, signs and publishes a
  named non-prerelease (keeping the git tag); main/dispatch keep the rolling
  'latest' prerelease. Body built with jq for safe escaping.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.forgejo/workflows/release.yml

@@ -4,6 +4,7 @@ on:
   workflow_dispatch: {}
   push:
     branches: [main]
+    tags: ['v*']
     paths:
       - '**.go'
       - 'go.mod'
@@ -97,40 +98,70 @@ jobs:
             xetup.exe
           echo "Signed and timestamped xetup.exe"
 
-      - name: Publish latest release
+      - name: Extract release notes from CHANGELOG.md
+        run: |
+          # On a version tag (v0.7) take that version's section; otherwise the
+          # latest released version section (first "## [<digit>"). Falls back to
+          # [Unreleased], then to a placeholder.
+          case "${{ github.ref }}" in
+            refs/tags/v*)
+              HEADER="## [$(echo "${{ github.ref }}" | sed 's#refs/tags/v##')]" ;;
+            *)
+              HEADER=$(grep -m1 -E '^## \[[0-9]' CHANGELOG.md 2>/dev/null || true) ;;
+          esac
+          [ -n "$HEADER" ] || HEADER="## [Unreleased]"
+          # Print the section body from HEADER (prefix match) until the next "## ".
+          awk -v h="$HEADER" '
+            index($0, h) == 1 { f = 1; next }
+            f && /^## / { exit }
+            f { print }
+          ' CHANGELOG.md > /tmp/notes.md
+          [ -s /tmp/notes.md ] || echo "See CHANGELOG.md." > /tmp/notes.md
+          echo "Release notes for '$HEADER':"; cat /tmp/notes.md
+
+      - name: Publish release
         env:
           TOKEN: ${{ secrets.FORGEJO_TOKEN }}
           API:   http://xetup-forgejo:3000/api/v1
           REPO:  ${{ github.repository }}
         run: |
           SHORT=$(echo "${{ github.sha }}" | cut -c1-7)
+          # Version tag -> named, non-prerelease; anything else -> rolling 'latest'.
+          case "${{ github.ref }}" in
+            refs/tags/*)
+              RELTAG=$(echo "${{ github.ref }}" | sed 's#refs/tags/##')
+              RELNAME="$RELTAG"; PRERELEASE=false ;;
+            *)
+              RELTAG="latest"; RELNAME="latest"; PRERELEASE=true ;;
+          esac
 
-          # Delete existing 'latest' release and tag to recreate cleanly
+          # Body = changelog section + build footer; built with jq so newlines and
+          # quotes are escaped safely.
+          BODY=$(printf '%s\n\n_Built from %s_' "$(cat /tmp/notes.md)" "$SHORT")
+          PAYLOAD=$(jq -n --arg tag "$RELTAG" --arg name "$RELNAME" \
+            --arg body "$BODY" --argjson pre "$PRERELEASE" \
+            '{tag_name:$tag, name:$name, body:$body, prerelease:$pre}')
+
+          # Replace any existing release for this tag. For rolling 'latest' also
+          # drop the git tag so it re-points to the new commit; never delete a
+          # real version tag.
           RID=$(curl -sf -H "Authorization: token $TOKEN" \
-            "$API/repos/$REPO/releases/tags/latest" | jq -r '.id // empty')
-          if [ -n "$RID" ]; then
-            curl -sf -X DELETE -H "Authorization: token $TOKEN" \
+            "$API/repos/$REPO/releases/tags/$RELTAG" | jq -r '.id // empty')
+          [ -n "$RID" ] && curl -sf -X DELETE -H "Authorization: token $TOKEN" \
             "$API/repos/$REPO/releases/$RID" || true
-          fi
-          curl -sf -X DELETE -H "Authorization: token $TOKEN" \
+          [ "$RELTAG" = "latest" ] && curl -sf -X DELETE -H "Authorization: token $TOKEN" \
             "$API/repos/$REPO/tags/latest" || true
 
-          # Create new 'latest' release
           RID=$(curl -sf -X POST \
-            -H "Authorization: token $TOKEN" \
-            -H "Content-Type: application/json" \
-            "$API/repos/$REPO/releases" \
-            -d "{\"tag_name\":\"latest\",\"name\":\"latest\",\"body\":\"Auto-built from ${SHORT}\",\"prerelease\":true}" \
-            | jq -r '.id')
+            -H "Authorization: token $TOKEN" -H "Content-Type: application/json" \
+            "$API/repos/$REPO/releases" -d "$PAYLOAD" | jq -r '.id')
 
-          # Upload xetup.exe
           curl -sf -X POST \
-            -H "Authorization: token $TOKEN" \
-            -H "Content-Type: application/octet-stream" \
+            -H "Authorization: token $TOKEN" -H "Content-Type: application/octet-stream" \
             "$API/repos/$REPO/releases/$RID/assets?name=xetup.exe" \
             --data-binary @xetup.exe
 
-          echo "Released xetup.exe (commit ${SHORT})"
+          echo "Released xetup.exe as '$RELNAME' (commit $SHORT)"
 
       - name: Update deploy.json
         # Cosmetic "last build" indicator. Requires docker.sock in the job