Codex App review diffs should support marking files as viewed

What variant of Codex are you using?

App

What feature would you like to see?

When reviewing Codex-made changes, I want a GitHub-style way to mark files or diff sections as viewed.

The key behavior is that once I have reviewed a file, it should stay collapsed/marked as read unless that file changes again. If a later agent turn edits the same file, only the new or changed parts should require re-review.

This matters when iterating with an agent before pushing or opening a PR. “Last turn” helps, but it is not the same thing: it assumes I fully reviewed every item from the previous turn before continuing. In practice I may review some files, ask for fixes, then need the app to preserve which parts are already done and which parts need fresh attention.

Additional information

GitHub’s pull request “Viewed” state is the reference workflow: reviewed files disappear from the active review surface until new changes invalidate that viewed state.