The Archives folder in the application server is not always accessible.
A button to upload directly in the CTS Archives page would be useful, especially for one-time uploads.
Moving forward (Stewardship 7.4 and above), Promote is the application that will used to manage code promotion in the stewardship tier. The ability to generate files to manage the promotion is on the roadmap. We'll be sure to add the ability to upload the file onto the destinaition instance via the frontend as a requirement.