Add Github Actions for publishing pages

.github/workflows/build.yml

@@ -0,0 +1,34 @@
+name: build
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+      - uses: actions/setup-java@v4
+        with:
+          java-version: 21
+          distribution: 'temurin'
+          cache: 'gradle'
+      - run: ./gradlew build --no-daemon
+      - uses: actions/upload-pages-artifact@v3
+        with:
+          path: web/dist/
+  deploy:
+    needs: build
+    runs-on: ubuntu-latest
+    if: github.ref == 'refs/heads/main' && github.repository == 'fumiX/sipgator-open'
+    permissions:
+      pages: write
+      id-token: write
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - id: deployment
+        uses: actions/deploy-pages@v4