Issue in /main/src/pages/get_started/app_builder_get_started/publish-app.md

This section is helpful, but there's no dedicated page or section describing how to modify an App Builder app _after_ it's been published the first time. There should be a simple workflow e.g. Revoke --> Modify --> Go to Approvals --> Submit again for review. It's confusing not to see the big blue "Submit for approval" button at the top on a revoked/modified app.

It's also unclear once published why the app is locked and read-only. It took almost 30 min of digging to try to figure out it was because it was published. Tooltip in the UI would be very helpful.

Start with main/src/pages/get_started/app_builder_get_started/publish-app.md and verify the post-publication workflow described by the issue. Document how to revoke, modify, return to Approvals, and submit again, and explain why a published app is locked or read-only; clarify whether the tooltip request belongs in separate UI work.

Written by the indexing model from the issue text.