feat: limit room remarks field to 200 characters to align with buspro

src/Form/Model/ParticipantDto.php

@@ -82,6 +82,10 @@ class ParticipantDto
     #[Assert\NotNull(message: 'Bitte ein Zimmer auswählen', groups: ['strict_required'])]
     public ?int $assignedRoomId = null;
 
+    #[Assert\Length(
+        max: 200,
+        maxMessage: 'Der Zimmerwunsch darf maximal {{ limit }} Zeichen lang sein'
+    )]
     public ?string $remarksRoom = null;
 
     public array $courses = [];