A tree-like description of all updates that happened to a stored state, to be included as a part
of a transaction receipt.
This structure is indexed (i.e. uses
IndexMaps where
Vecs could be used) for convenience
and performance, since both the source (i.e. Track) and the sink (i.e. Database and API) operate
on indexed structures too.
This structure maintains partial information on the order of operations (please see individual
fields for details), since the end users care about it. Please note that this means multiple
instances of
StateUpdates can represent the same transform of state store (i.e. differing
only by order of some operations), and hence it is not 100% “canonical form”.