fix: allow updating room assignments in edit mode

src/Form/Model/ParticipantEditDto.php

@@ -132,6 +132,11 @@ class ParticipantEditDto
     #[Assert\Callback(groups: ['booking_create', 'booking_edit'])]
     public function validateEmailUniqueness(ExecutionContextInterface $context): void
     {
+        // Skip for internal agency bookings — staff use shared placeholder emails
+        if ($this->bookingContext->isInternalAgencyBooking()) {
+            return;
+        }
+
         // Skip validation for applicant (index 0) - applicant's email can be shared with dependents
         if (true === $this->participant->isApplicant()) {
             return;