Add GitHub Actions CI CD pipeline

.github/workflows/deploy.yml

@@ -0,0 +1,61 @@
+
+name: Calculator CI/CD Pipeline
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 20
+
+      - name: Check Project Files
+        run: |
+          test -f index.html
+          test -f styles.css
+          test -f script.js
+
+      - name: Check JavaScript Syntax
+        run: node --check script.js
+
+      - name: Prepare Website Artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: .
+
+  deploy:
+    if: github.event_name == 'push'
+    needs: build-and-test
+    runs-on: ubuntu-latest
+
+    permissions:
+      pages: write
+      id-token: write
+
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+
+    steps:
+      - name: Setup GitHub Pages
+        uses: actions/configure-pages@v5
+
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4