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>

.env

@@ -0,0 +1,60 @@
+# In all environments, the following files are loaded if they exist,
+# the latter taking precedence over the former:
+#
+#  * .env                contains default values for the environment variables needed by the app
+#  * .env.local          uncommitted file with local overrides
+#  * .env.$APP_ENV       committed environment-specific defaults
+#  * .env.$APP_ENV.local uncommitted environment-specific overrides
+#
+# Real environment variables win over .env files.
+#
+# DO NOT DEFINE PRODUCTION SECRETS IN THIS FILE NOR IN ANY OTHER COMMITTED FILES.
+# https://symfony.com/doc/current/configuration/secrets.html
+#
+# Run "composer dump-env prod" to compile .env files for production use (requires symfony/flex >=1.2).
+# https://symfony.com/doc/current/best_practices.html#use-environment-variables-for-infrastructure-configuration
+
+###> symfony/framework-bundle ###
+# Committed default is the server (prod) profile. On the dev box, override in
+# .env.local: APP_ENV=dev, a real APP_SECRET, and a local DATABASE_URL.
+APP_ENV=prod
+APP_SECRET=
+APP_SHARE_DIR=var/share
+# CIDR ranges the Nginx Proxy Manager / Docker network live in (loopback +
+# RFC1918). Lets Symfony trust X-Forwarded-* from the reverse proxy.
+TRUSTED_PROXIES=127.0.0.1,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16
+###< symfony/framework-bundle ###
+
+###> symfony/routing ###
+# Configure how to generate URLs in non-HTTP contexts, such as CLI commands.
+# See https://symfony.com/doc/current/routing.html#generating-urls-in-commands
+DEFAULT_URI=https://dmtools.fvandenberg.nl
+###< symfony/routing ###
+
+###> doctrine/doctrine-bundle ###
+# Format described at https://www.doctrine-project.org/projects/doctrine-dbal/en/latest/reference/configuration.html#connecting-using-a-url
+#
+# In Docker (servers) the host is the `database` service and these parts come
+# from docker-compose.yml / .env.local. On the dev box, point DATABASE_URL at
+# your local MariaDB in .env.local, e.g.:
+#   DATABASE_URL="mysql://root:@127.0.0.1:3306/dmtools?serverVersion=10.10.2-MariaDB&charset=utf8mb4"
+DB_HOST=database
+DB_PORT=3306
+DB_NAME=dmtools
+DB_USER=dmtools
+DB_PASSWORD=ChangeMe
+DB_ROOT_PASSWORD=ChangeMeRoot
+DB_SERVER_VERSION=mariadb-12.3.2
+DATABASE_URL="mysql://${DB_USER}:${DB_PASSWORD}@${DB_HOST}:${DB_PORT}/${DB_NAME}?serverVersion=${DB_SERVER_VERSION}&charset=utf8mb4"
+###< doctrine/doctrine-bundle ###
+
+###> symfony/messenger ###
+# Choose one of the transports below
+# MESSENGER_TRANSPORT_DSN=amqp://guest:guest@localhost:5672/%2f/messages
+# MESSENGER_TRANSPORT_DSN=redis://localhost:6379/messages
+MESSENGER_TRANSPORT_DSN=doctrine://default?auto_setup=0
+###< symfony/messenger ###
+
+###> symfony/mailer ###
+MAILER_DSN=null://null
+###< symfony/mailer ###