Scaffold Symfony 8 app with Bootstrap/DataTables and Docker stack

- Symfony 8.1 webapp skeleton on PHP 8.5 (AssetMapper/importmap, no Node)
- Form-login gate: User entity, security.yaml, SecurityController,
  app:user:create command, initial migration (user + messenger_messages)
- Bootstrap 5 + DataTables layout (base/login/home templates); any
  table.datatable is auto-initialised
- trusted_proxies/headers wired for the shared Nginx Proxy Manager
- Docker (servers only): docker-compose.yml (php:8.5-fpm-alpine,
  nginx:1.30-alpine, mariadb:12.3; host ports 8085/3310; external
  docker_default network) + docker/{Dockerfile,php.ini,nginx,setup.sh,restart.sh}
- .env with CHANGEME placeholders (no secrets), .gitattributes enforces
  LF so the deploy scripts stay runnable on Linux

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docker/php/php.ini

@@ -0,0 +1,20 @@
+; dmtools - PHP-FPM runtime tuning (servers).
+
+expose_php = Off
+memory_limit = 256M
+max_execution_time = 60
+date.timezone = Europe/Amsterdam
+
+upload_max_filesize = 20M
+post_max_size = 21M
+
+realpath_cache_size = 4096K
+realpath_cache_ttl = 600
+
+opcache.enable = 1
+opcache.enable_cli = 0
+opcache.memory_consumption = 128
+opcache.max_accelerated_files = 20000
+opcache.validate_timestamps = 0
+opcache.preload_user = www-data
+opcache.preload = /var/www/html/config/preload.php