chore: add GitHub Actions workflow for testing across multiple Node.js versions

.github/workflows/publish.yml

@@ -1,4 +1,4 @@
-name: Publish to NPM
+name: Publish
 
 on:
   release:
@@ -9,7 +9,7 @@ permissions:
   contents: read
 
 jobs:
-  publish:
+  npm:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6

.github/workflows/test.yml

@@ -0,0 +1,24 @@
+name: Test
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [18, 20, 22, 24]
+    steps:
+      - uses: actions/checkout@v6
+      - uses: actions/setup-node@v6
+        with:
+          node-version: ${{ matrix.node-version }}
+          cache: "npm"
+      - run: npm ci
+      - run: npm run typecheck
+      - run: npm run lint
+      - run: npm run test:run