[Feature Request] Make Plan Mode exit confirmation default option configurable

Feature Request

Make Plan Mode confirmation dialog default option configurable

When exiting Plan Mode, the confirmation dialog shows 'Yes, clear context and auto-accept edits' as the first/default option.
This can lead to accidental context clearing.

Request: Add a setting (e.g., 'planModeDefaultOption' or similar) to configure which option is pre-selected by default in the
ExitPlanMode confirmation dialog.

Use case: Users who rarely want to clear context would prefer 'Yes, auto-accept edits' (without clearing) as the default, with
'clear context' as a secondary option.

This would improve the UX by letting users customize the confirmation flow to match their typical workflow."

Environment Info

• Platform: darwin
• Terminal: alacritty
• Version: 2.1.14
• Feedback ID: 11a95aee-fac6-4d97-92e6-ea83856504fa