Create a ViewComponent for DuoPro Trials selection form

DuoPro trial lead form logic is currently scattered across the controller and view layers, reducing maintainability.

As part of our broader initiative to make trial views more modular, we want to convert this form to use ViewComponents.

• Convert the DuoPro trial selection form to use ViewComponents
• Improve testability through component isolation
• Maintain consistency with the patterns established in Ultimate trials - see 505669
• Associated MR