Add heylogs badge workflow

.github/workflows/heylogs.yml

@@ -0,0 +1,33 @@
+name: Heylogs
+
+on: [ push ]
+
+jobs:
+  badge-job:
+    if: startsWith(github.repository, 'nbbrd/') && startsWith(github.ref, 'refs/heads/develop')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout source code
+        uses: actions/checkout@v4
+
+      - name: Setup Java
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: 21
+          cache: 'maven'
+
+      - name: Scan changelog
+        run: mvn -B -ntp -U com.github.nbbrd.heylogs:heylogs-maven-plugin::scan -Dheylogs.output.file=scan.json -Dheylogs.format.id=json
+
+      - name: Create badges endpoint json
+        run: |
+          mkdir heylogs
+          jq '{schemaVersion: 1, label: "unreleased changes", message: "#\(.[0].summary.unreleasedChanges)", color: "E05735", logoColor: "white", namedLogo: "keepachangelog"}' scan.json > heylogs/unreleased-changes.json
+          
+      - name: Deploy badges endpoint json
+        uses: peaceiris/actions-gh-pages@v4
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./heylogs
+          destination_dir: ./heylogs