Add CI workflow

Fixes #7

.github/workflows/ci.yml

@@ -0,0 +1,28 @@
+name: CI
+
+on:
+  push:
+    branches: ['main']
+  pull_request:
+    types: [opened, synchronize]
+
+jobs:
+  checks:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: pnpm/action-setup@v4
+        with:
+          version: latest
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 'lts/*'
+          cache: 'pnpm'
+
+      - run: pnpm i --frozen-lockfile
+
+      - run: pnpm run lint
+
+      - run: pnpm run check