Different time signatures with the same total rhythmic duration may incorrectly be treated as equivalent for repeat courtesies

Issue type

Engraving bug (incorrect score rendering)

Description with steps to reproduce

1. Open the attached test score.
2. Add a time signature (e.g. 4/4) to the bar following the end repeat barline.
   RESULT: time signature and appropriate repeat courtesy is added as expected.
3. Undo, then attempt to add a 3/4 time signature at the same place. Notice that total rhythmic duration (3/4) is the same as is being repeated to (6/8).
   RESULT: The 3/4 time signature is not added.
4. Open Format > Style > Clefs, key and time signatures > Clefs, key & time signatures at repeats and jumps and uncheck At repeats, only show changes before the barline.
5. Repeat step 3.
   RESULT: Now the 3/4 time signature and appropriate repeat courtesies are drawn as expected.
6. In the Style dialog, check At repeats, only show changes before the barline.
   EXPECTED: No change to the notation (because the time signatures for the repeat and the subsequent measures are different).
   ACTUAL: A single 3/4 time signature is drawn before the repeat barline.

Supporting files, videos and screenshots

https://github.com/user-attachments/assets/406e8144-0a60-42fb-be82-0e036dbbb0ba

In which versions of MuseScore Studio is this issue present?

4.5.0-latest nightly

Regression

No.

Operating system

Ubuntu 24.04.4 LTS

Additional context

This appears never to have worked correctly.

Checklist

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