feat: split summary DTOs into typed sub-objects

src/Service/BookingRoomSelectionService.php

@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace App\Service;
 
 use App\BusProNet\Model\Room;
+use App\Form\Model\RoomGroupsDto;
 
 /**
  * Groups room data for booking steps.
@@ -13,10 +14,8 @@ class BookingRoomSelectionService
 {
     /**
      * @param array<int, Room> $rooms
-     *
-     * @return array{by_pax: array<int, Room>, by_room: array<int, Room>}
      */
-    public function groupRoomsBySelectionType(array $rooms): array
+    public function groupRoomsBySelectionType(array $rooms): RoomGroupsDto
     {
         $groups = [
             Room::SELECTION_TYPE_BY_PAX => [],
@@ -35,6 +34,9 @@ class BookingRoomSelectionService
         uasort($groups[Room::SELECTION_TYPE_BY_PAX], static fn (Room $a, Room $b): int => $a->maxPax <=> $b->maxPax);
         uasort($groups[Room::SELECTION_TYPE_BY_ROOM], static fn (Room $a, Room $b): int => $a->maxPax <=> $b->maxPax);
 
-        return $groups;
+        return new RoomGroupsDto(
+            byPax: $groups[Room::SELECTION_TYPE_BY_PAX],
+            byRoom: $groups[Room::SELECTION_TYPE_BY_ROOM],
+        );
     }
 }