Typed snapshot returned by Flow policy reads and mutations.
generation is allocated monotonically by FerricStore. Pass a snapshot's
generation as expected_generation to perform a compare-and-swap update.
Summary
Types
@type generation() :: non_neg_integer()
@type state_mode() :: :fifo | :parallel | nil
@type t() :: %FerricStore.Flow.PolicySnapshot{ extensions: map(), generation: generation(), governance: map() | nil, indexed_attributes: [binary()] | nil, indexed_state_meta: binary() | [binary()] | nil, max_active_ms: pos_integer() | :infinity | nil, mode: state_mode(), retention: map() | nil, retry: map() | nil, state: binary() | nil, states: %{optional(binary()) => map()}, type: binary(), version: term() }