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>

templates/base.html.twig

@@ -0,0 +1,47 @@
+<!DOCTYPE html>
+<html lang="en" data-bs-theme="dark">
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <title>{% block title %}dmtools{% endblock %}</title>
+        <link rel="icon" href="data:image/svg+xml,<svg xmlns=%22http://www.w3.org/2000/svg%22 viewBox=%220 0 128 128%22><text y=%221.1em%22 font-size=%22104%22>🎲</text></svg>">
+
+        {% block stylesheets %}{% endblock %}
+
+        {% block javascripts %}
+            {% block importmap %}{{ importmap('app') }}{% endblock %}
+        {% endblock %}
+    </head>
+    <body class="d-flex flex-column">
+        {% block navbar %}
+        <nav class="navbar navbar-expand-lg bg-body-tertiary border-bottom">
+            <div class="container">
+                <a class="navbar-brand" href="{{ path('app_home') }}">🎲 dmtools</a>
+                {% if app.user %}
+                    <div class="d-flex align-items-center gap-3">
+                        <span class="navbar-text small">{{ app.user.userIdentifier }}</span>
+                        <a class="btn btn-outline-secondary btn-sm" href="{{ path('app_logout') }}">Log out</a>
+                    </div>
+                {% endif %}
+            </div>
+        </nav>
+        {% endblock %}
+
+        <main class="app-main flex-grow-1">
+            <div class="container">
+                {% block flashes %}
+                    {% for label, messages in app.flashes %}
+                        {% for message in messages %}
+                            <div class="alert alert-{{ label == 'error' ? 'danger' : label }} alert-dismissible fade show" role="alert">
+                                {{ message }}
+                                <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
+                            </div>
+                        {% endfor %}
+                    {% endfor %}
+                {% endblock %}
+
+                {% block body %}{% endblock %}
+            </div>
+        </main>
+    </body>
+</html>