Resources hangs on Models with no system-id attached

[Tethik]

When opening the resources tab on a threat model without a system-id, it fetches for a long time then returns an error.
This should be handled nicer.

[Tyouxik]

It can be handled with a message informing that resources are not available for standalone models, or removing the resource tab.
Prevent fetching or return an empty list from the backend to avoid misusing resources.

[Tethik]

I think technically resources could be available on standalone models, it depends on how/where they are fetched from. I'd let the backend decide, just ensure it's nicely rendered on the client when the list is empty.