Add a completion confirmation to the Guest Portal’s Registration section

Display a clear confirmation in the Guest Portal’s Registration section once the guest has completed all required registration tasks and nothing remains pending. Suggested message: “You’re all done! Your registration is complete, and there’s nothing else you need to do right now.” The message should reflect the guest’s current registration status and update if additional required tasks become pending. Expected benefit: Reassure guests that they’ve completed their registration, remove uncertainty about outstanding steps, and reduce unnecessary follow-up questions to hosts or Support.