feat: Permettre au super admin de se connecter et accéder à son dashboard

Le super admin (table super_admins, master DB) ne pouvait pas se connecter
via /api/login car ce firewall n'utilisait que le provider tenant. De même,
le JWT n'était pas enrichi pour les super admins, l'endpoint /api/me/roles
les rejetait, et le frontend redirigeait systématiquement vers /dashboard.

Un chain provider (super_admin + tenant) résout l'authentification,
le JwtPayloadEnricher et MyRolesProvider gèrent désormais les deux types
d'utilisateurs, et le frontend redirige selon le rôle après login.

backend/src/SuperAdmin/Infrastructure/Api/Processor/CreateEstablishmentProcessor.php

@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\SuperAdmin\Infrastructure\Api\Processor;
+
+use ApiPlatform\Metadata\Operation;
+use ApiPlatform\State\ProcessorInterface;
+use App\SuperAdmin\Application\Command\CreateEstablishment\CreateEstablishmentCommand;
+use App\SuperAdmin\Application\Command\CreateEstablishment\CreateEstablishmentHandler;
+use App\SuperAdmin\Infrastructure\Api\Resource\EstablishmentResource;
+use App\SuperAdmin\Infrastructure\Security\SecuritySuperAdmin;
+use Override;
+use Symfony\Bundle\SecurityBundle\Security;
+
+/**
+ * @implements ProcessorInterface<EstablishmentResource, EstablishmentResource>
+ */
+final readonly class CreateEstablishmentProcessor implements ProcessorInterface
+{
+    public function __construct(
+        private CreateEstablishmentHandler $handler,
+        private Security $security,
+    ) {
+    }
+
+    /**
+     * @param EstablishmentResource $data
+     */
+    #[Override]
+    public function process(mixed $data, Operation $operation, array $uriVariables = [], array $context = []): EstablishmentResource
+    {
+        /** @var SecuritySuperAdmin $user */
+        $user = $this->security->getUser();
+
+        $result = ($this->handler)(new CreateEstablishmentCommand(
+            name: $data->name,
+            subdomain: $data->subdomain,
+            adminEmail: $data->adminEmail,
+            superAdminId: $user->superAdminId(),
+        ));
+
+        $resource = new EstablishmentResource();
+        $resource->id = $result->establishmentId;
+        $resource->tenantId = $result->tenantId;
+        $resource->name = $result->name;
+        $resource->subdomain = $result->subdomain;
+        $resource->databaseName = $result->databaseName;
+        $resource->status = 'active';
+
+        return $resource;
+    }
+}