fix: return updated layout data if child uses parent

[eltigerchino]

fixes #9355

This PR changes the server data to return the updated layout data from a layout node if a child load function uses parent. Previously, the child load function would receive the updated data from parent, but the layout node would still return the stale data.

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[dummdidumm]

I don't know how I feel about changing this. If the parent load function does not have anything in it that makes it officially rerun, I don't think we should let it rerun indirectly via await parent(). If await parent() happens to create new data then that's more of a misuse of the parent load function. We only need to re-request the parent data on the server because there's no way to pass the parent data back into the load function endpoint when we call it, so the parent knowledge has to be re-constructed. On the client that's not the case with the universal loaders, so it would make a confusing difference.

[eltigerchino]

We only need to re-request the parent data on the server because there's no way to pass the parent data back into the load function endpoint when we call it, so the parent knowledge has to be re-constructed.

Should we try to pursue some form of this (passing the parent data from the client to the server) so that the parent data is consistent?

If await parent() happens to create new data then that's more of a misuse of the parent load function.

There could also be cases where it isn't a misuse. For example: an admin updates a user's settings, causing the parent load function to return new data when the parent data is reconstructed. This would cause the layout data to be stale while the child load uses fresh data.