Add required checks for PRs

Sets up GitHub Actions workflow for CI. Closes #43.

Author: austinlparker

.github/workflows/ci.yml

@@ -0,0 +1,21 @@
+name: CI
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20.x'
+          cache: 'npm'
+      - run: npm ci
+      - run: npm run build
+      - run: npm run lint