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>

assets/styles/app.css

@@ -0,0 +1,25 @@
+/* dmtools project styles. Bootstrap + DataTables (bs5) are imported from app.js. */
+
+body {
+    min-height: 100vh;
+}
+
+main.app-main {
+    padding-top: 1.5rem;
+    padding-bottom: 3rem;
+}
+
+.navbar-brand {
+    font-weight: 600;
+    letter-spacing: 0.02em;
+}
+
+.login-card {
+    max-width: 24rem;
+    margin: 8vh auto 0;
+}
+
+/* Let DataTables' controls breathe inside a Bootstrap card. */
+table.dataTable {
+    width: 100% !important;
+}