feat!: change of ErpEntityInterface

The ErpEntityInterface interface has been expanded to include customer files and the reversal method.
ErpEntityInterface can also be "deleted". However, these cannot be deleted correctly in 90% of cases, hence reversal.

BREAKING CHANGE: ErpEntityInterface extended

src/QUI/ERP/ErpEntityInterface.php

@@ -99,4 +99,23 @@ public function setCustomer(array|QUI\Interfaces\Users\User $User);
      * @return array
      */
     public function toArray(): array;
+
+    /**
+     * Cancel the entity
+     * (Reversal, Storno, Cancel)
+     *
+     * @param string $reason
+     * @param User|null $PermissionUser
+     * @return ?ErpEntityInterface
+     */
+    public function reversal(
+        string $reason = '',
+        QUI\Interfaces\Users\User $PermissionUser = null
+    ): ?ErpEntityInterface;
+
+    public function addCustomerFile(string $fileHash, array $options = []): void;
+
+    public function clearCustomerFiles(): void;
+
+    public function getCustomerFiles(): array;
 }

src/QUI/ERP/Process.php

@@ -60,7 +60,7 @@ protected function table(): string
     /**
      * Return all entities which are connected to this process
      *
-     * @return array
+     * @return ErpEntityInterface[]
      */
     public function getEntities(): array
     {