feat: initialize project with Symfony, React, and Tailwind CSS setup

- Add package.json with development and production dependencies
- Create postcss.config.js for Tailwind CSS integration
- Implement AdminController for handling admin routes
- Add admin index template with React root element
- Create base template for consistent layout
- Configure TypeScript with tsconfig.json
- Set up Webpack configuration for asset management

.gitignore

@@ -46,3 +46,10 @@
 
 # Composer
 /composer.phar
+
+###> symfony/webpack-encore-bundle ###
+/node_modules/
+/public/build/
+npm-debug.log
+yarn-error.log
+###< symfony/webpack-encore-bundle ###