feat(shared-data): add deck schema v6

This schema contains a concept of "locating features" for addressable
areas. These locating features are things that constrain the position of
labware loaded on top of the addressable area. The presence of a
locating feature indicates that the addressable area can contain deck
items. Which locating feature is available constrains which labware can
be loaded; different labware define different locatable features (for
instance, their back left or front left corners, or the outer surface of
one of their wells).

Closes EXEC-80