ci: release automatically when master carries an unreleased package.json version

On push to master the workflow now checks whether tag v<version> exists and,
if not, creates the tag and the GitHub release with the Windows installer.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017Wn5VX9HNbJ7N54hR24u9Y

.github/workflows/windows-release.yml

@@ -42,7 +42,14 @@ jobs:
       - name: Read version
         id: ver
         shell: bash
-        run: echo "version=$(node -p "require('./package.json').version")" >> "$GITHUB_OUTPUT"
+        run: |
+          version=$(node -p "require('./package.json').version")
+          echo "version=$version" >> "$GITHUB_OUTPUT"
+          if git ls-remote --exit-code --tags origin "refs/tags/v$version" >/dev/null 2>&1; then
+            echo "released=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "released=false" >> "$GITHUB_OUTPUT"
+          fi
       - run: npm run build
       - name: Package Windows EXE
         run: npx electron-builder --win --publish never
@@ -57,7 +64,7 @@ jobs:
             out/latest.yml
           if-no-files-found: error
       - name: Publish GitHub release
-        if: startsWith(github.ref, 'refs/tags/v') || github.event_name == 'workflow_dispatch'
+        if: startsWith(github.ref, 'refs/tags/v') || github.event_name == 'workflow_dispatch' || (github.event_name == 'push' && github.ref == 'refs/heads/master' && steps.ver.outputs.released == 'false')
         uses: softprops/action-gh-release@v2
         with:
           tag_name: v${{ steps.ver.outputs.version }}