Migrate to TypeScript

.editorconfig

@@ -0,0 +1,7 @@
+root = true
+
+[*]
+charset = utf-8
+indent_size = 2
+indent_style = space
+trim_trailing_whitespace = true

.github/workflows/ci.yml

@@ -0,0 +1,34 @@
+name: CI
+
+on:
+  push:
+    branches: [master, develop]
+  pull_request:
+    branches: [master]
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 'lts/*'
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Install Playwright browsers
+        run: npx playwright install chromium
+
+      - name: Run linter
+        run: npm run lint
+
+      - name: Run unit tests
+        run: npm test

.vscode/settings.json

@@ -0,0 +1,4 @@
+{
+  "eslint.codeActionsOnSave.mode": "problems",
+  "eslint.useFlatConfig": true,
+}