fix: applicant split in edit mode, drop create-mode agency checks

tests/Form/Service/ParticipantEmailFieldHandlerTest.php

@@ -4,7 +4,9 @@ declare(strict_types=1);
 
 namespace App\Tests\Form\Service;
 
+use App\BusProNet\Model\Booking;
 use App\BusProNet\Model\Travel;
+use App\BusProNet\XmlLoader\AgencyLoader;
 use App\Form\Model\BookingDto;
 use App\Form\Model\ParticipantDto;
 use App\Form\Service\ParticipantDateOfBirthFieldHandler;
@@ -79,6 +81,30 @@ class ParticipantEmailFieldHandlerTest extends TestCase
         $this->assertSame('[email protected]', $bookingDto->participants[0]->email);
     }
 
+    public function testEditModeNeverPreFills(): void
+    {
+        $bookingDto = $this->createBookingDto();
+        $bookingDto->booking = new Booking();
+
+        $this->handler->processField(['email' => ''], $bookingDto, 1);
+
+        $this->assertNull(
+            $bookingDto->participants[1]->email,
+            'participant[0] is not reliably the applicant in edit mode, and a blank may be intended'
+        );
+    }
+
+    public function testEditModeLeavesAnInternalAgencyChildWithoutEmail(): void
+    {
+        $bookingDto = $this->createBookingDto();
+        $bookingDto->booking = new Booking();
+        $bookingDto->agencyCode = AgencyLoader::INTERNAL_AGENCY_CODE;
+
+        $this->handler->processField(['email' => ''], $bookingDto, 1);
+
+        $this->assertNull($bookingDto->participants[1]->email);
+    }
+
     public function testHandlerRunsAfterDateOfBirth(): void
     {
         $this->assertSame(