Crash or huge memory leak on opening score with Staff Type Change (added twice)

Issue type

Crash or freeze

Description with steps to reproduce

This issue is based on a report from musescore.org (problematic file fallingtidesrise-percussion.mscz )
Normally when user adds Staff Type Change, Musescore writes it to the file like this:

<StaffTypeChange>
  <StaffType group="percussion">
    <name>perc1Line</name>
    <keysig>0</keysig>
    </StaffType>
</StaffTypeChange>

However in some cases a "zeroed" record (or many records) may be added which looks like this:

<StaffTypeChange>
  <StaffType group="">
     <lines>0</lines>
     <lineDistance>0</lineDistance>
     <mag>0</mag>
     <stepOffset>132474896</stepOffset>
     <slashStyle>242</slashStyle>
     <stemless>242</stemless>
     <timesig>0</timesig>
     <color r="0" g="0" b="0" a="0"/>
     <durations>0</durations>
     <durationFontName>MuseScore Tab Modern</durationFontName>
     <durationFontSize>0</durationFontSize>
    ...
  </StaffType>
</StaffTypeChange>

When saved, the project cannot be opened again - Musescore crashes/hangs/memory leaks.
If <mag>0</mag> removed, the project can be opened again.

Tested with Musescore 4.4.2 and 4.5.0 master.

The only way I could reproduce this state from scratch:

1. add two StaffTypeChange elements to the same measure in parts.
2. Close/reopen score
3. Remove one StaffTypeChange element.
4. If remaining StaffTypeChange element looks empty (without lines inside), save score
5. Close/reopen project - > Musescore freezes/crashes + memory leaks.
   It may take a few tries to reproduce the situation. Opening the properties panel for the StaffTypeChange element may help.
   Attaching a template to reproduce from scratch
   StaffTypeChangeIssue5_gh.mscz.zip

Supporting files, videos and screenshots

https://github.com/user-attachments/assets/62b77cc2-03da-4b3e-aae6-d56142d3338e

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

MuseScore Studio version (64-bit): 4.5.0-242870307, revision: github-musescore-musescore-0c45d97

Regression

The crash also occurs in 3.6.2

Operating system

windows 10, but macs are affected too

Additional context

Another report https://musescore.org/en/node/378646 with scores:
La Morte (version 2)_0.zip
La Morte_0.zip

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