Add indicator when adding extension repos to note that something in the background is happening

[rancher-max]

Is your feature request related to a problem? Please describe.

When adding extensions, there is no indication that they are being added. Refreshing the page sometimes has them shows up, but if the server is slower then it doesn't always work if you refresh too quickly and it can lead to confusion on whether the last action (to add Partner Extensions, for example) was successful.

Describe the solution you'd like

It would be nice if there was a loading indicator on the page to indicate that something is happening. Also, once they are available, it would be nice if the extension cards showed up in real time instead of needing to refresh or navigate away from the page and back.

Describe alternatives you've considered

Any sort of indication would be fine that helps show a request was received and rancher is working on fulfilling it.

Additional context

This is not high priority at all, but would be a nice enhancement. See below video for additional context as to the problem. I show navigating to a different page and back ends up working here and producing the cards, but until doing that there is nothing. Note that there is also a 500 error that I believe might be part of the problem here -- perhaps reaching out to the API to retrieve the data too fast?

Screen.Recording.2025-11-26.at.1.14.27.PM.mov

500 error request and response:

• Request: GET /v1/catalog.cattle.io.clusterrepos/partner-extensions?link=index
• Response: {"type":"error","links":{},"code":"ServerError","message":"configmaps \"\" not found","status":500,"type":"error"}