Include cross-staff arpeggio in chord shape

[XiaoMigros]

Resolves: #25995

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Forgot to check the vtests!

[miiizen]

Adding the arpeggio to the skyline creates unwanted space between the staves, as can be seen in the vtests. If we add the arpeggio to the skyline, we need to make sure it isn't taken into account in stave spacing calculations.