Reclassify base-movement warps as bulk exits

[Zannick]

For the purposes of A* search, we want to better distinguish non-Euclidean movements (warping across the map) from edges we otherwise want to include. Plus "base movement" has always been awkward.

Not sure at the moment whether these should be a new type in the rust, or if we should literally create Exit definitions for them at every applicable spot (that might affect condensing, come to think of it).