feat: split summary DTOs into typed sub-objects

tests/Service/BookingRoomSelectionServiceTest.php

@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace App\Tests\Service;
 
 use App\BusProNet\Model\Room;
+use App\Form\Model\RoomGroupsDto;
 use App\Service\BookingRoomSelectionService;
 use PHPUnit\Framework\TestCase;
 
@@ -27,8 +28,9 @@ class BookingRoomSelectionServiceTest extends TestCase
 
         $groups = $this->service->groupRoomsBySelectionType($rooms);
 
-        $this->assertSame([10, 12], array_keys($groups[Room::SELECTION_TYPE_BY_PAX]));
-        $this->assertSame([11], array_keys($groups[Room::SELECTION_TYPE_BY_ROOM]));
+        $this->assertInstanceOf(RoomGroupsDto::class, $groups);
+        $this->assertSame([10, 12], array_keys($groups->byPax));
+        $this->assertSame([11], array_keys($groups->byRoom));
     }
 
     private function createRoom(int $id, string $label, int $maxPax): Room