QoL: Expanded plan should scroll to beginning of plan #689

When clicking the "Expand plan" button, I think it should auto-scroll to the beginning of the plan, which is what I have to do manually every single time, because the reason to expand is to read it, at least for me 🤓

Codex does the same, and it's nothing urgent, just wanted to include it here because I think this would make the experience much nicer 🥰

Thanks for this amazing app, love Codex, but it's way too slow, especially starting a new thread Expand plan