ci: add automated quality checks

.github/workflows/node-ci.yml

@@ -0,0 +1,42 @@
+name: Node.js CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: node-ci-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  quality:
+    name: Type-check, test, and build
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    steps:
+      - name: Check out source
+        uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Type-check
+        run: npm run typecheck
+
+      - name: Run tests
+        run: npm test
+
+      - name: Build package
+        run: npm run build