Phase 0 : scaffolding complet

- Structure monorepo (backend Symfony, frontend React/Vite)
- Docker : FrankenPHP + PostgreSQL/PostGIS + Redis + Traefik labels
- Caddyfile, Dockerfile, .env.example, .gitignore
- MapLibre GL JS + react-map-gl installés
- Roadmap mise à jour

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker/php/Caddyfile

@@ -0,0 +1,25 @@
+{
+    frankenphp
+    order php_server before file_server
+}
+
+:80 {
+    root * /app/public
+
+    # Assets Symfony
+    handle /bundles/* {
+        file_server
+    }
+
+    # SPA React (fichiers statiques buildés dans public/spa/)
+    handle /spa/* {
+        file_server
+    }
+
+    # Tout le reste → Symfony (front controller index.php)
+    handle {
+        php_server
+    }
+
+    encode gzip
+}