Property extraction reaches the driveItem asynchronously, so the GET
step previously waited only until any extraction facet key appeared and
a separate step then validated the full schema, which could run on a
partial payload and fail intermittently. The GET and the status check
stay plain steps; a new explicit Then step re-fetches the item until
the response satisfies the expected schema (a partial never matches) or
the WaitHelper timeout elapses.