feat: split booking between participants and applicant

addresses #869f2q1vu

src/Form/Service/ParticipantAssignedRoomFieldHandler.php

@@ -203,7 +203,7 @@ class ParticipantAssignedRoomFieldHandler extends AbstractParticipantFieldHandle
 
             // Add notification for unassigned participant
             // For internal agency bookings, first participant is not the applicant
-            $isApplicant = $participant->isApplicant() && false === $bookingDto->isInternalAgencyBooking();
+            $isApplicant = $participant->isApplicant() && $bookingDto->isFirstParticipantApplicant();
             $participantLabel = $isApplicant ? 'Anmelder:in' : 'Teilnehmer:in '.($participant->index + 1);
             $participant->addNotification('warning', sprintf('%s wurde von %s entfernt', $roomLabel, $participantLabel));