Add wishlist feature and admin/analytics endpoints

Introduces a Wishlist model with related serializers, admin, and API endpoints for users to manage favorite products. Adds admin endpoints for wishlist management and a placeholder AnalyticsViewSet for future business intelligence features. Refactors permissions for commerce views, updates product filtering and ordering, and improves carrier and payment logic. Also includes minor VSCode settings and Zasilkovna client import updates.

backend/commerce/tasks.py

@@ -107,7 +107,7 @@ def notify_about_missing_payment(order = None, user = None, **kwargs):
     
     pass
 
-
+@shared_task
 def notify_refund_items_arrived(order = None, user = None, **kwargs):
     if not order or not user:
         raise ValueError("Order and User must be provided for notification.")