feat: add customer details fields to Purchase model and request, implement checkout process with cart clearing

app/Domains/Purchase/Resources/PurchaseResource.php

@@ -36,6 +36,10 @@ class PurchaseResource extends JsonResource
             'status' => $this->status,
             'payment_status' => $this->payment_status,
             'payment_method' => $this->payment_method,
+            'dni' => $this->dni,
+            'telefono' => $this->telefono,
+            'nombre_apellido' => $this->nombre_apellido,
+            'email' => $this->email,
             'items' => PurchaseItemResource::collection($items),
             'subtotal' => $this->formatMoney($subtotal),
             'total' => $this->formatMoney($total),