Improve download mechanism #326
Description
Currently downloading attestations and pieces of evidence from the CAS has many limitations. You can use the CLI chainloop artifact download or our new endpoint #307 to download artifacts by digest but the actual process in the backend has some limitations.
Once you try to download an asset we redirect the user to download it to the default CAS backend from the current organization. Meaning that you'll not be able to download an item if
- a) The CAS backend has changed Being able to download an artifact even if default CAS backend changed #268
- b) The artifact belongs to another org that's not your current one.
The goal of this task is for supporting a way to overcome these two issues, in other words, to be able to download any artifact that an user has access to, from any CAS backend in any org the are members of.
After this task we will enable this other capability #263
### Tasks
- [x] Download from any org and any backend #268
- [x] Public download of evidences and attestations #263