Frontend for view registrations page

# Story:
AS A Transplant Games registrant,
I WANT to see all my registrations in one place,
SO THAT I can track my progress and manage my family's registrations.

## Details:
Create dashboard page displaying all user's registrations with names and status indicators.

**Acceptance Criteria:**
- List/card layout showing registrant names and status
- Visual status badges (draft vs submitted)
- "Add New Registration" button
- Click registration to edit (placeholder link for now)
- Loading and empty states
- Mobile responsive design