Add CI workflow

Author: ThatGuyNick05

.github/workflows/ci.yml

@@ -0,0 +1,35 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  build-test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: 🧱 Checkout code
+        uses: actions/checkout@v4
+
+      - name: 📦 Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 20
+
+      - name: 📥 Install dependencies
+        run: npm ci
+
+      - name: 🛠️ Build project
+        run: npm run build
+
+      - name: 🧹 Lint code
+        run: npm run lint
+
+      - name: 🎨 Check formatting
+        run: npm run format
+
+      - name: 🧪 Run tests
+        run: npm test