[MU4] Fix #9995: Double/halve note duration skips values in note entry mode

[RomanPudashkin]

Resolves: #9995

[bkunda]

Tested in MacOS and Windows. Shortcuts work well across standard and TAB staves.
One related change I did notice (from MS3 behaviour) is that the 0 key no longer enters an open string in tablature staves (instead, it enters a rest). Not sure if this was changed somewhere along the line, but I think it should continue to enter open string "0" -- particularly as this key is also necessary to enter the "10" fret.
@RomanPudashkin let me know if this can be addressed in this PR, or if you'd like me to raise this separately :-)

[RomanPudashkin]

One related change I did notice (from MS3 behaviour) is that the 0 key no longer enters an open string in tablature staves

@bkunda I can reproduce this bug in the master, so let's rise it as a separate issue

[bkunda]

Sure! I'll do this now