feat: pre-flight check of agency bookings

addresses #869bqxr4q

src/BusProNet/Model/Address.php

@@ -5,6 +5,7 @@ declare(strict_types=1);
 namespace App\BusProNet\Model;
 
 use Symfony\Component\Validator\Constraints as Assert;
+use function Symfony\Component\String\u;
 
 /**
  * Represents a physical address with street, postal code, city, and country information.
@@ -29,6 +30,21 @@ class Address
     #[Assert\NotBlank(message: 'Bitte angeben', groups: ['personal_data'])]
     public ?string $country = null;
 
+    /**
+     * Normalizes legacy string data loaded from API/session sources.
+     *
+     * Trims whitespace and converts empty strings to null so load-time audits
+     * and form hydration see canonical values.
+     */
+    public function normalize(): void
+    {
+        $this->street = $this->normalizeNullableString($this->street);
+        $this->postCode = $this->normalizeNullableString($this->postCode);
+        $this->city = $this->normalizeNullableString($this->city);
+        $this->district = $this->normalizeNullableString($this->district);
+        $this->country = $this->normalizeNullableString($this->country);
+    }
+
     /**
      * Converts the address to API payload format.
      *
@@ -47,4 +63,15 @@ class Address
             'land' => $this->country,
         ];
     }
+
+    private function normalizeNullableString(?string $value): ?string
+    {
+        if (null === $value) {
+            return null;
+        }
+
+        $trimmed = u($value)->trim()->toString();
+
+        return '' === $trimmed ? null : $trimmed;
+    }
 }