Revamp the configuration UI with an interactive editor that supports inline text editing, navigation, and field validation, replacing the previous sequential prompts. Add GitLab pull request creation support via the `glab` CLI, and extend back navigation to all interactive menus for a consistent user experience.
Reviewed-on: #4
Extract duplicate menu rendering logic from `index.ts` into a new `src/menu.ts` module, providing generic `selectOne` and `selectMany` functions. This reduces code duplication, improves maintainability, and adds consistent UI controls display across the commit flow and platform selection.
Reviewed-on: #3
Mplan