This renames the basemost resource properties, id and urn, to
names that are less likely to conflict with properties that real
resources will want to use, pid and upn (provider ID and Universal
Pulumi Name, respectively).
I actually ran into this with the current bridge work. An alternative
solution would be to require derived resources to pick different names,
however this is unfortunate because usually they are more "user-facing"
than ours. Another alternative is to not hijack the object properties
at all, but that too is problematic because we use these properties
during the evaluation of plans and deployments.
This seems like a reasonable middle ground.