Investigate and potentially fix fireball collision mechanics

[LlewVallis]

I've had reports that fireball collision does not work identically on CK as it does in OMW. This needs to be investigated fixed if there are indeed discrepancies.

One particular case that needs attention is fireballs when placed such that they are overlapping blocks. An example of the interesting behavior they have on CK can be seen here.

[LlewVallis]

Some people have shared some information about CK fireball mechanics with me, I'll replicate it below. None of this is confirmed, make of it what you will.

xorizontal says:

I know they have differently sized effective hitboxes based on what they hit/what hits them
3 blocks for a olayer punching them
1 block for a prohectile hitting them
and 1 pixel for hitting a block
I think it's that
also, if they directly hit a tnt, they give it velocity in that direction and ignite it fully [4 second fuse], usually
however if they hit adjacent blocks, but the rng also gets the tnt, it goes instantly [simultaneously]
I think the probability of igniting/destroying adjacent blocks is increased the lower the blast resistence of the block it hits
hence shooting at 2 tnt almost always makes an instant [simultaneous] explosion
while shooting at a rs block with a tnt next to it is less consistent
when hitting an entity e.g. player it can ignite nearby tnt
but I don't think it can when it hits a lit tnt

iRobo says:

I will expand on what xorizontal said, if the tnt is a moving block entity when the fireball hits then it'll simultaneously light the affected tnt blocks, but if it hits a solid tnt block then apart from igniting the solid tnt blocks within the blast radius using the normal random fuse (whatever wiki states 0.5-1.5s iirc) and the moving block entity tnt's silmultaneously, it will light the solid tnt that it directly hit (i.e. if there are several solid tnt blocks that the hitbox collides with at the same time, then the one colliding with the midpoint on the side of the fireball's hitbox will be affected) with a full fuse