chore: streamline property naming

src/Form/Model/ParticipantDto.php

@@ -71,11 +71,6 @@ class ParticipantDto
     // License plate for participants with parking (optional, visible only when parking is selected)
     public ?string $licensePlate = null;
 
-    // Deprecated properties for backward compatibility - will be removed in future version
-    public ?Service $transportationServiceTo = null;
-    public ?Service $transportationServiceFro = null;
-    public ?Pickup $pickup = null;
-
     public static function fromPersonalData(PersonalData $personalData): static
     {
         $instance = new static();
@@ -98,6 +93,11 @@ class ParticipantDto
         return $instance;
     }
 
+    public function isApplicant(): bool
+    {
+        return 0 === $this->index;
+    }
+
     public function isCanceled(): bool
     {
         return 'S' === $this->status;