chore: add parents to error nodes

[teemingc]

This is a prerequisite to closing #9703 and #12578

#13234 failed because we were missing two things:

1. Determining if page options for a node are dynamic or static
2. Parent node info for error nodes to determine their final page options

The first has been solved by our static analyser which sets it to null if it wasn't statically analysable.
The second is solved by this PR. I've chosen to split it out so that it's easier to review, but if it only makes sense to do in the actual PRs that closes both issues, let me know.

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[elliott-with-the-longest-name-on-github]

lgtm, thanks