Feature Request/Idea: Improve error messages for BagIt handler

[abujeda]

Overview of the Feature Request
The recently created BagIt file handler extracts the files from a zip file and validates the BagIt checksums from the manifest.

We have reviewed the error messages presented to the user by the handler when problems are found and would like to implement some improvements:

• Error message placement should be closer to the upload files section.
• Error message should disappear after a valid upload is completed.
• Error message wording should be clearer to the end user on what the problem is and how to fix it.
• Error messages should handle multiple BagIt packages uploaded at the same time.

What kind of user is the feature intended for?
Curator, Depositor, Guest. Any user uploading a BagIt zip file.

What inspired the request?
User testing in a AWS environment

What existing behavior do you want changed?
The error messages for the BagIt file handler

Any brand new behavior do you want to add to Dataverse?
No

Any related open or closed issues to this feature request?
Relates to the original issue where BagIt file handler was introduced: #8608

[abujeda]

New error location:

[abujeda]

PR created: #8792

This is ready for review @scolapasta @pdurbin