add gh action to make sure repo is buildable on pr

.github/workflows/build-on-pr.yml

@@ -0,0 +1,25 @@
+name: Build on Pull Request
+
+on:
+  pull_request:
+    branches: ['main']
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    - name: Set up Node.js
+      uses: actions/setup-node@v3
+      with:
+        node-version: '20' # Use the Node.js version you're working with
+        cache: 'npm' # Use the Node.js version you're working with
+
+    - name: Install dependencies
+      run: npm ci
+
+    - name: Build
+      run: npm run build