Remove HandInteractEvent and sub events

[ImMorpheus]

We have 3 way to get the hand used in an interact event:

1. a method: HandInteractEvent#getHandType
2. specific sub events: X.MainHand and X.OffHand
3. EventContextKeys.USED_HAND

This is overly verbose, unnecessary and confusing to a degree.
This PR removes 1. and 2.

[dualspiral]

1. may need to return(ish, in a different form), as per Enhance Visibility of EventContextKey Usage #1975

[Zidane]

@ImMorpheus Status on this?

[ImMorpheus]

Nothing to add on my end.

EDIT: I didn't mean to close it