This accepts a Wonka source and throws a promise
if the result is not resolving immediately. This
is done for suspensen and will also limit the
source to a single result.

If the source pushes a value synchronously it
is let through and won't throw a promise, which
also will subsequently let through more values
from the source.

This can be used on the client and the server;
On the server it can start caching results,
while on the client it retrieves cached results
from a rehydrated cache.

This was a whoopsie..
The order of cachedOps$ and forwardedOps$ in ssrExchange
is now reversed. It has been completely swapped to indicate
that the order is important, but only the reverse merge
matters.

Essentially on the client we would delete the result from
the cache in cachedOps$ but then check for whether it was
cached again in forwardedOps$. This would unfortunately
duplicate the operation.