Fix #65241: add property and style for position of multimeasure rest numbers

[IsaacWeiss]

Resolves: https://musescore.org/en/node/65241

Adds an additional Inspector property for the vertical position of multimeasure rest numbers, and a corresponding linked style parameter.

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[ecstrema]

Yay! What would be useful (and not difficult to implement I believe) would be the interval based measure numbers.

I believe that there is an issue associated with it, but I can't find it.

[ecstrema]

It could be worth separating MM rests into 2 elements: one for the number and one for the line. Needs some investigation...

[IsaacWeiss]

Yay! What would be useful (and not difficult to implement I believe) would be the interval based measure numbers.

I believe that there is an issue associated with it, but I can't find it.

That would be part of a Google Summer of Code Project I am considering. :-)

[RobFog]

Rebase needed.

[IsaacWeiss]

Added the collision avoidance, as seen in this GIF:

[IsaacWeiss]

I believe all review comments have been addressed.