UX: multi-stage form shows mouse pointer on the stages when they cannot be clicked

### Current Behavior

The stage titles in the progress bar show cursor-pointer when hovered - but clicking on them does nothing.

Screenshot with a drawn-on mouse pointer cos my screenshoting software doesn't pickup the cursor...

### 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