Force chunk load on elevation check

[Tetrino]

When BlockState is called on a block that is within a chunk that has yet to be loaded, it will always return nil. This results in a situation wherein the height found by the elevation check will always return -63Y in these cases.

This commmit attempts to fix this by forcing an asynchronous chunk load of the destination chunk before elevation is calculated.

This is most apparent in ChunkyBorder, wherein a worldwrap teleport would attempt to position the player in a chunk that had yet to be loaded, or even exist, always teleporting them to -63Y

See: pop4959/ChunkyBorder#91

[Tetrino]

Of note but not within scope of this commit is that isSolid() is currently deprecated and at some point, these functions should be refactored to rely on isSolidBlock(BlockView, BlockPos) .

[Warriorrrr]

I don't believe this to be the correct solution to this problem, world.getHeight and world.getBlockState both already load the chunk if it isn't loaded already, there's also no guarantee that the chunk future will finish at any time.

I've previously added the getElevationAtAsync method which you could override on the fabric/(neo)forge platforms, chunkyborder already uses that to avoid doing a sync chunk load.