Lagging in big scores when reinstating alterations (near to the end of score)

Issue type

Crash or freeze

Description with steps to reproduce

This issue happens in "Input by note name mode" (and in "page view").

When inputting a note which has an alteration already in key signature, or a natural sign where there's no alteration in key signature (both necessary as cautionary alterations after a barline), MuseScore in incredibly lagging in writing the requested note.

This happens in big projects and, weirdly enough, it is not present in the first measures, but increasingly worsens if you try in subsequent measures. I'm talking about already complete projects: adding a note like that in m.1 gives no problem, adding it in m.1000 will give a 2/3 seconds lag.

Also, "Re-pitch existing notes" doesn't have this problem at all, and can repitch with reinstated alterations with no lag, no matter how big the project is and which measure are you writing in.

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(from https://github.com/musescore/MuseScore/issues/28059#issuecomment-2910209785)

1. Open Reicha - Ouerture D major Quintuple Time_CHANGED.zip
2. Go to measure 488
3. Input two quarter F# notes with toggled sharps
4. Compare with regular F# notes (without showing sharps)

https://github.com/user-attachments/assets/6d0ca8ee-5f74-4db5-b19f-48cbdf9cd077

Supporting files, videos and screenshots

This is just an example, in this specific measure I could use D♯ vs. D♮ and the result would be the same.
This is a +1000 measures orchestral score. I tried the same thing on a couple of much smaller orchestral scores, and on a 700 measures string quartet, and the lag is shorter but still present (~1 sec).

What is the latest version of MuseScore Studio where this issue is present?

4.5.2

Regression

I was unable to check

Operating system

Windows 11

Additional context

This is probably unrelated (or maybe it is, I'm not a developer, I can't know), but please remember that the new "Input by duration" mode can't even add reinstated alterations at all (https://github.com/musescore/MuseScore/issues/27311)

Checklist

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