Codex App: add per-finding Fix buttons to review output

Variant

App

What feature would you like to see?

When Codex shows review output in the desktop app, each actionable review finding should have a visible Fix button directly underneath it.

Today, the user has to translate the review output back into a follow-up prompt such as fix this, fix the first issue, or fix all. That works, but it adds friction and can be ambiguous when there are multiple findings. The app already has the structured review output in front of the user, so the common next action should be available from the review UI itself.

Expected behavior:

1. Each actionable review finding has a Fix button.
2. Clicking Fix starts a follow-up turn scoped to that specific finding.
3. If there are multiple findings, the app can also offer Fix all where appropriate.
4. The follow-up prompt should preserve enough context that Codex knows which finding is being addressed without the user needing to retype or reference it manually.

Why this matters

Review output is most useful when it can quickly turn into a fix loop:

1. Run review.
2. Inspect findings.
3. Click Fix under the finding worth addressing.
4. Re-run review.

This is especially useful in the app because review findings are already rendered as UI elements, not just plain terminal text. The app can provide a more direct workflow than relying on typed numbered references.

Related

This is related to #26361, but that issue is CLI-focused and asks for numbered findings so users can type prompts like fix 1. The app likely wants a more explicit UI affordance: per-finding action buttons such as Fix, and possibly Explain or Fix all.