Approval workflow

The flow that takes a design from "submitted for review" to "approved final" with a clear record of who approved what.

An approval workflow is the set of states and transitions for client sign-off: submitted → in review → changes requested → approved. A good workflow stamps the exact version that got approved, notifies the designer the moment it happens, locks the approved version from accidental edits, and keeps a record per file of who approved and when.