Improve behavior when copying and pasting notes with tremolo

Task description
(@oktophonie edit)

Let's say we have a two-note tremolo lasting four beats, in a 4/4 bar, and we want to paste it into bars of a different length, or perhaps just to a different place within another 4/4 bar:

If we try to paste the 4/4 bar into the following two 2/4 bars, currently we get this nonsensical, corrupted result:

At a bare minimum - and in complex cases this may remain necessary as a fallback if all else fails - we should just lose the tremolo and keep the two underlying notes, with their original rhythms (i.e. two minims):

But better would be to create a new two note tremolo over the original number of beats, which means breaking it at each barline or any other necessary subdivision, i.e.:

Or if the time signature were 3/4, for example:

Or if you were to paste into the middle of the second beat of a 4/4 bar:

(etc)

See also: https://github.com/musescore/MuseScore/issues/14600