Move input cursor past tied chords

[XiaoMigros]

Currently, the input cursor does not take into account tied notes when calculating the new position:

Now, the cursor places itself at the end of a tied chord:

Worth mentioning that not all input methods calculate the new cursor position via the method changed in this PR, perhaps it's worth standardising this behavior?

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[bkunda]

@XiaoMigros sorry for not checking this earlier.
Can you please rebase and I'll test it? Thanks!