Dev-mode warning: `Warning: Only plain objects can be passed to Client Components from Server Components. Classes or other objects with methods are not supported.`

This seems to be caused by `queryRef.toPromise()`.

I'd love to keep the function in there in the long term, but we might need to ask the React team to make that possible. Meanwhile I'll probably (temporarily?) remove the function.

([Reported in Discord](https://discord.com/channels/1022972389463687228/1262792222659842109))

Start by locating the queryRef.toPromise() implementation in the Next.js App Router integration and reproduce the warning in development mode. Check the reported Server Components and Client Components boundary, then verify that the warning no longer appears after the proposed temporary change while the surrounding query behavior remains covered.

Written by the indexing model from the issue text.