Show voice assignment shortcuts in inspector

[XiaoMigros]

Resolves: #31611

Unfortunately requires a minor change to the UI Components, made in the first commit.

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[avvvvve]

I think this needs a rebase (am I using that term correctly here?) so that this fix is incorporated. Currently can't access properties properly in this build.

[cbjeukendrup]

Rebased!

am I using that term correctly here?

Yes!

[avvvvve]

@XiaoMigros Nice! Thanks for including the shortcuts for all voices too in the context menu:

A couple small requests:

1. I know the actual shortcuts are called 'Use voice 1' 'Use voice 2' etc., but I think we can just label them 'Voice 1' 'Voice 2' etc. for the individual voices.
   

2. For a dynamic on a single-staff instrument, I don't see a tooltip for the 'All' button. When hovering, it should say 'All voices on instrument' and show the Alt+Ctrl+0 / Opt+Cmd+0 shortcut.

[XiaoMigros]

@avvvvve should all be accounted for!

[avvvvve]

Thanks!

Just tested with a screenreader too, and while it's leagues better than what we had before when focusing on those buttons (it used to just say 'undefined'), I think we can improve what gets read.

Generally, when a radio button option that's part of a properties control is focused on by the screen reader, what's read is the property name followed by the button name, like this:

Position Above, radio button

...but for the 'Voice assignment' buttons, the property name is not read before the button names:

Could we make it so the screenreader says the following for each button:

All:

• For multi-staff instruments, when the 'parent' button is hovered, ideally it would read the name of whichever of the two options is currently selected:
  • Voice assignment, All voices on instrument, button
  • Voice assignment, All voices on this staff only, button
• For single-staff instruments, it should just read:
  • Voice assignment, All voices on instrument, radio button
    • if we can't make it say 'radio button' (as opposed to 'button' as it says now), that's okay for now.

Individual voices:

• Voice assignment, Voice 1, radio button
• ...
• Voice assignment, Voice 4, radio button

[avvvvve]

Logged my last comment as a follow up: #32586

Approving the rest!