This is quite a breaking change, but I think it is beneficial due to the large amount of usage of this class.
I originally intended just to remove the allocations of the two delegates handling the `Changed` flow internally, but as nothing was really using the bindables for anything more than a general "point has changed" case, this felt like a better direction.
The goal of the visibility increase is to help in cases where timing is
an issue (by showing the approach circle etc.). This doesn't need to
apply to catch.
@smoogipoo interested as to whether you agree with this one. Visually it
looks better to me but it does change the behaviour for only osu!catch,
so I'm not 100% confident on it.
Closes#13367.