This change rearanges serialization of properties in a few ways:
* Mirror the asset/archive serialization that we use in the fabric
itself, so that we can recover the nature of these objects on
both side of the RPC boundary.
* Wait for promises to settle before marshaling resource properties.
This allows for I/O in creating a resource's state. Note that
we of course still do not block awaiting resolution of resource
output properties during dry runs (planning), because they will
never resolve. This is distinctly different from promises.
* Add tests for the above.
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