[Agent] Make approving commands and providing text input more noticeable

[marcel-tan]

"Allow Run command?" is not very noticeable at the moment because 1) I'm focusing on the animated loading icon for "Executing [run command]..." and 2) the text at the bottom of TUI is usually the hotkey hints "scroll, top/bottom, stop".

We could leave the hotkey hints as is and then add the CTA for running commands or providing text input above it to make it more clear.

[jy-tan]

Ideally the "approve", "approve all" etc buttons can be more prominent instead of being in the help text row, perhaps immediately display a text box here too.

To think about this further, check how Claude Code does this.