Have the frontend making the API call to sara directly

[mrica-equinor]

Describe the improvement you would like to see
Currently the frontend makes a call to the backend to retrieve the images from the sara anon storage account and visualized account. Then this image is downloaded by the backend and fowarded as a file to the frontend where it is cached.

It has been discussed that an improvement to this code would be to have the frontend directly call the sara api and the download of the image happens on the frontend.

This task can be split in two as well:

1. Have the download of the blob happen in the frontend
2. Have the frontend call sara instead of calling the backend which calls sara

How will this change existing functionality?
Functionality is the same, it's just a better code approach.

How will this improvement affect the current Threat Model?
Leave blank for maintainers to fill out if you are uncertain about this.

[andchiind]

The SARA backend in this case should return a SAS token that let's the user download the blob directly, with a low time to live.