chore: add workflow to format using prettier

.github/workflows/format.yml

@@ -0,0 +1,21 @@
+name: Format
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 18
+          cache: 'npm'
+      - run: npm ci
+      - name: Format
+        run: |
+          npm run format

package.json

@@ -20,6 +20,8 @@
     "test:ci:changed": "nx affected -t test --base=origin/main --head=HEAD",
     "test-all-versions": "nx run-many -t test-all-versions",
     "changelog": "lerna-changelog",
+    "format": "prettier --check $(git ls-files '*.ts')",
+    "format:fix": "prettier --write $(git ls-files '*.ts')",
     "lint": "nx run-many -t lint && npm run lint:readme && npm run lint:markdown",
     "lint:fix": "nx run-many -t lint:fix && npm run lint:markdown:fix",
     "lint:deps": "npx --yes [email protected] --dependencies --production --tags=-knipignore",