ci: add prettier to CI

.github/workflows/prettify.yml

@@ -0,0 +1,14 @@
+name: Prettify Code
+on: [pull_request, push]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20.x
+          cache: 'npm'
+      - run: npm ci
+      - run: npx prettier . --check