Direction-based choosing of landing spots for items, knockback, etc

[issuebotaudinowho[bot]]

Discord: iambadatlife#0 <@205553191985610753>

FR: Change the protocol for same tile occupancy when dealing with knockback to reduce the directional dependence of knockback inflicting moves.

https://docs.google.com/document/d/1CZqgtDVJFgGubhrRv2X8G8sG87YLGQrRCMwa_95EmRI/edit?usp=sharing