Add scramble image viewer with show/hide control

Users asked for visual scramble diagrams that can be shown or hidden.

Feedback source:
- Add an image of the scramble that you can hide/show using a button.
- Draw scramble for all events.
- There is only 3x3 but we need another event.

Acceptance ideas:
- Add a show/hide control for scramble visualization.
- Start with supported events and fail gracefully for unsupported events.
- Keep scramble text available even when the image is hidden.
- Consider how this interacts with completed solve review/history.