[Windows Desktop] Restore inline comments on Plan mode plans

Summary

Please restore inline comments/annotations on generated Plan mode plans in the Codex desktop app.

What changed

An earlier Codex workflow allowed me to select a specific part of a generated plan and attach a comment directly to that plan section. That made iterative planning feel much more precise: I could comment on one decision, constraint, or acceptance criterion without restating the whole plan.

In the current Windows desktop experience, the native annotation affordance is no longer available on the plan itself. I can work around it by asking Codex to save the plan as Markdown, but that loses the native Plan mode presentation and makes the workflow less fluid.

Requested behavior

• Keep the generated plan as a first-class Plan mode item.
• Allow selecting a plan heading or paragraph and attaching an inline comment.
• Send the selected plan context together with the comment on the next turn.
• Preserve the existing plan structure when Codex revises the plan.

Why this matters

This was an excellent interaction for design reviews, implementation specifications, and other work where the user wants to steer individual decisions before coding starts. It reduced ambiguity and made planning feel collaborative rather than like editing a long assistant message.

Codex desktop on Windows. Exact app version is not visible from the current task.