ci: run build and unit tests on PRs and main

.github/workflows/ci.yml

@@ -0,0 +1,31 @@
+name: CI
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build
+        run: npm run build
+        env:
+          NODE_OPTIONS: --max-old-space-size=12288
+
+      - name: Unit tests
+        run: npm run test:unit
+        env:
+          NODE_OPTIONS: --max-old-space-size=12288