Add preload flag to clientLoader

[dadamssg]

This adds an optional preload flag to clientLoader. If this is set, the route loader is automatically opted into the single-fetch request. There is an RFC here.

export async function clientLoader({ serverLoader }: Route.ClientLoaderArgs) {
  // Resolves data from single-fetch request because of `preload` flag.
  // Does not initiate new request.
  let serverData = await serverLoader()
  return {
    rows: enrichWithClientData(serverData.rows)
  }
}
clientLoader.preload = true // new flag

This is a WIP. I'm not sure how to best get the fact that there is a preload on the clientLoader in the vite plugin.

[changeset-bot]

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Latest commit: b1f0d0d

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[brophdawg11]

Closing for now but linked to the RFC