“Next” disappears on smaller screen sizes when scrolled

### Current Behavior

When creating a hosted instance, working through the instance creation workflow, “next” disappears on smaller screen sizes when scrolled.

### Expected Behavior

_No response_

### Steps To Reproduce

_No response_

### Environment

- FlowFuse version:
- Node.js version:
- npm version:
- Platform/OS:
- Browser:

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate

Start with the hosted instance creation workflow and reproduce the issue at a smaller screen size while scrolling. Locate the “Next” control and verify that it remains visible and usable throughout the workflow at smaller sizes.

Written by the indexing model from the issue text.