Fix media file storage path and permissions

- Fix MEDIA_ROOT path to match Docker volume mount (/app/myproject/media)
- Update docker-compose.yml volume mounts to match MEDIA_ROOT
- Add setup_directories() function in entrypoint.sh to create media directories with proper permissions
- Add logging to TenantAwareFileSystemStorage for debugging
- Fix is_returned flag logic improvements (from previous work)

myproject/inventory/views/sale.py

@@ -94,10 +94,20 @@ class SaleDeleteView(LoginRequiredMixin, DeleteView):
     template_name = 'inventory/sale/sale_confirm_delete.html'
     success_url = reverse_lazy('inventory:sale-list')
 
-    def form_valid(self, form):
+    def delete(self, request, *args, **kwargs):
         sale = self.get_object()
+        order = sale.order
+        
+        result = super().delete(request, *args, **kwargs)
+        
+        # Обновляем флаг заказа после удаления Sale
+        if order:
+            from inventory.signals import update_is_returned_flag
+            update_is_returned_flag(order)
+        
         messages.success(
-            self.request,
+            request,
             f'Продажа товара "{sale.product.name}" отменена.'
         )
-        return super().form_valid(form)
+        
+        return result