Timeline blueprint is glitched when the hit object has negative duration.
Negative duration is unwanted anyways so placement implementation is fixed instead of supporting it in timline blueprint.
While osu!catch also implements a distance snap grid, it doesn't rely on
`GetBeatSnapDistanceAt` (unlike osu!), therefore it can't have the
"distance spacing" multiplier yet.
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.