feat: export component contexts

[jer3m01]

[ANovokmet]

This would be useful for my components. Often there is an inaccessible piece of state I need, eg. I need to get the displayed items in a filtered-out combobox.

[MAST1999]

I just ran into this while trying to hide a 'x' clear button from multi select items in the combo box if it is read-only.

But I think this would be really helpful in general.