"Across Staves" time signature creates unselectable part of every bar

Issue type

UX/Interaction bug (incorrect behaviour)

Description with steps to reproduce

1. On a multi instrument part, Enable Style > Clefs, keys and time signatures > Time Signatures > Across Staves
2. Try to click in the first part of a bar low down in the score

Expected: a range selection is created for the bar

Actual: the time signature (which may be off screen) is selected.

This is very surprising. I didn't even realise anything was being selected until I started preparing this issue report. It felt like the click was just doing nothing for some bars.

Supporting files, videos and screenshots

https://github.com/user-attachments/assets/6acd2eda-9357-491c-8fa7-d55d434d22be

In which versions of MuseScore Studio is this issue present?

OS: macOS Sequoia (15.7.7), Arch.: arm64, MuseScore Studio version (64-bit): 4.7.4-260706075, revision: github-musescore-musescore-7688c00

Regression

I was unable to check

Operating system

macOS

Additional context

No response

Checklist

• This report follows the guidelines for reporting bugs and issues
• I have verified that this issue has not been logged before, by searching the issue tracker for similar issues
• I have attached all requested files and information to this report
• I have attempted to identify the root problem as concisely as possible, and have used minimal reproducible examples where possible

Reproduce the issue in a multi-instrument part by enabling Style > Clefs, keys and time signatures > Time Signatures > Across Staves, then click the first part of a bar low in the score. Trace the selection behavior for that click; done means a range selection is created for the bar instead of selecting the possibly off-screen time signature.