feat: add cron scheduling and update services

- Added go-crond library to Dockerfile for task scheduling
- Created schedule service in compose.yaml with go-crond
- Added cron configuration file: docker/cron/laravel
- Updated README.md
- Improved service configurations with health checks
- Switched to base frankenphp image

docker/cron/laravel

@@ -0,0 +1 @@
+* * * * * appuser cd /var/www && /usr/local/bin/php artisan schedule:run >> /var/www/storage/logs/cron.log 2>&1