refactored code

Signed-off-by: Maurice Preuß (envoyr) <hello@envoyr.com>

src/Id/Concerns/HasBillable.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace Anikeen\Id\Concerns;
+
+use Anikeen\Id\Contracts\Billable;
+use Illuminate\Database\Eloquent\Model;
+
+trait HasBillable
+{
+    protected Billable|Model $billable;
+
+    public function setBillable(Billable|Model $billable): self
+    {
+        $this->billable = $billable;
+
+        return $this;
+    }
+
+    public function getBillable(): Billable|Model
+    {
+        return $this->billable;
+    }
+}