Feature request: Enable nova data façade to support partial implementations of the interface

Hi,

Scenario
Org Explorer is an Apollo graphql people experience (aka.ms/orgexplorer) where my team integrated People Highlights (ref on scenario here). Our integration package is implementing the nova data interface.

Background info
Today highlights are integrated in the host app (OrgX) root query. OrgX is a NON-nova host app. Highlights type is embedded inside OrgX root query making the implementation of useLazyLoadQuery difficult. so far we opted for implementing the following methods, while querying happens inside the host app and then it's passed down as props:

• useMutation - this works well because highlights are not embedded in the orgx root mutation (it's decoupled)
• useFragment - we are relying on the default implementation where data passed via props is mirrored.

Challenge
Since data is passed down via props, we can't ensure proper usage of useFragment unless we extract from the Fragment$key the data and forcefully cast it to a ref.

const highlightRef = props.personaHighlightFragment[" $data"] as unknown as {
    readonly " $fragmentRefs": FragmentRefs<"HighlightsFragment">;
  };

where personaHighlightFragment is a Nova fragment constructed this way (on the host app)

 // Convert from Apollo fragment to Nova(Relay) fragment
  const personaHighlightFragment: NovaHighlightsFragment$key = {
    " $fragmentRefs": { HighlightsFragment: true },
    " $data": personaHighlight as NovaHighlightsFragment,
  };

Ask: Enable nova to handle such object transformations when data is not fetched via useLazyLoadQuery but rather passed via props.

Start by reviewing the Nova data interface and the useFragment, useMutation, and useLazyLoadQuery entry points described in the issue. Determine how partial implementations and props-passed data should be represented without the current casts. Done should mean the Apollo-to-Nova transformation works for this scenario and is covered by appropriate tests.