Add automated deployment of gh-pages

Author: che-wf

.github/workflows/deploy-demo.yml

@@ -0,0 +1,35 @@
+name: Deploy Demo to GitHub Pages
+
+on:
+  push:
+    paths:
+      - 'gh-pages/**'
+    branches:
+      - main
+  workflow_dispatch:
+
+jobs:
+  build-and-deploy:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: gh-pages
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '18'
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Build demo
+        run: npm run build
+
+      - name: Deploy to GitHub Pages
+        run: npm run deploy
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}