Special-case error message to add extra information

The Derivation parser and old ATerm unfortunately leaves few ways to get
nice errors when an old version of Nix encounters a new version of the
format. The most likely scenario for this to occur is with a new client
making a derivation that the old daemon it is communicating with cannot
understand.

The extensions we just created for dynamic derivation deps will add a
version field, solving the problem going forward, but there is still the
issue of what to do about old versions of Nix up to now.

The solution here is to carefully catch the bad error from the daemon
that is likely to indicate this problem, and add some extra context to
it.

There is another "Ugly backwards compatibility hack" in
`remote-store.cc` that also works by transforming an error.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>

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