feat(3p/nix): Add gRPC definitions for worker protocol r/1215

Adds initial gRPC definitions for the Nix worker protocol, which is
currently defined messily across the following files:

    src/libstore/worker-protocol.hh
    src/libstore/remote-store.cc
    src/nix-daemon/nix-daemon.cc

The protocol definition is basically a big enum with the signatures of
the calls being implicit in the various client/server implementation
functions.

The definitions in this file are slowly reversed from these implicit
signatures, and are likely to contain an error or two which will be
weeded out when this is taken into use.

Only a handful of the calls are included in this commit, it is
intended to get us up and running first.

Change-Id: Ibc9b2ab4b91a064c8935f09f7ac72bb8150fb476
Reviewed-on: https://cl.tvl.fyi/c/depot/+/926
Reviewed-by: isomer <isomer@tvl.fyi>
Tested-by: BuildkiteCI

0 files changed, 0 insertions, 0 deletions