feat(commercial) : validation back de la relation + suivi de revue MR (ERP-119)

- validation serveur « relation choisie => FK obligatoire » : champ transitoire
  relationType (non persiste) + Assert\Callback portant la 422 sur distributor /
  broker, que le back ne pouvait pas deriver des seules FK nullable
- mutualisation des payloads d'ecriture clients : new.vue consomme buildMainPayload
  / buildAddressPayload / buildRibPayload (fin de la duplication create/edit)
- COMMENT ON TABLE client_address : ajout des types Courtier / Distributeur
  (catalogue + migration Version20260609120000)
- tests : violationsByPath remonte dans AbstractCommercialApiTestCase (fin des
  copies inline) + couverture de la nouvelle RG relation

tests/Module/Commercial/Api/ClientAddressTest.php

@@ -241,10 +241,7 @@ final class ClientAddressTest extends AbstractCommercialApiTestCase
         ])->toArray(false);
 
         self::assertResponseStatusCodeSame(422);
-        $byPath = [];
-        foreach ($body['violations'] ?? [] as $v) {
-            $byPath[$v['propertyPath']] = $v['message'];
-        }
+        $byPath = $this->violationsByPath($body);
         self::assertArrayHasKey('billingEmailSecondary', $byPath);
     }
 
@@ -402,10 +399,7 @@ final class ClientAddressTest extends AbstractCommercialApiTestCase
         ])->toArray(false);
 
         self::assertResponseStatusCodeSame(422);
-        $byPath = [];
-        foreach ($body['violations'] ?? [] as $v) {
-            $byPath[$v['propertyPath']] = $v['message'];
-        }
+        $byPath = $this->violationsByPath($body);
         self::assertArrayHasKey('isProspect', $byPath);
         self::assertSame('Le type d\'adresse est obligatoire.', $byPath['isProspect']);
     }
@@ -484,10 +478,7 @@ final class ClientAddressTest extends AbstractCommercialApiTestCase
         ])->toArray(false);
 
         self::assertResponseStatusCodeSame(422);
-        $byPath = [];
-        foreach ($body['violations'] ?? [] as $v) {
-            $byPath[$v['propertyPath']] = $v['message'];
-        }
+        $byPath = $this->violationsByPath($body);
         self::assertArrayHasKey('isProspect', $byPath);
         self::assertSame('Une adresse Courtier ne peut pas avoir d\'autre type.', $byPath['isProspect']);
     }