MS4 Stem invisibilty is ignored when importing musicxml

[MortenHe]

Issue type

Import/export issue

Bug description

When making a note inivisible (notehead + stem) and exporting it to musicxml the note is visible again when re-importing the musicxml.
The notehead part has alreday been fixed by #21187
The stem is still visible on import.

Steps to reproduce

1. Create a score with an invisible note (notehead + stem)
2. Export as musicxml
3. Import musicxml -> stem is visible

Screenshots/Screen recordings

No response

MuseScore Version

4.2

Regression

Yes, this used to work in MuseScore 3.x and now is broken

Operating system

Windows 10 Pro

Additional context

No response

[Jojo-Schmitz]

Not a Mu3 regression, the same Todo in the code there

Difficulty is (or might be): the stem should only be invisible if all notes of thet chord are

[rettinghaus]

Another problem here is that MuseScore differentiates between chords with invisible stems and without stems. If the MusicXML says <stem>none</stem> I'd guess it means a chord without a stem?

[Jojo-Schmitz]

Yes, IMHO the entire concept of invisible elements is unknown in MuscXML