flake.nix reads from VERSION instead of hardcoding; Makefile gains a version target that syncs VERSION from the latest git tag and injects it into go build ldflags. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Define GardenSync service with 5 RPCs: PushManifest, PushBlobs, PullManifest, PullBlobs, Prune. Messages for manifest, entries, blob chunks (64 KiB streaming), and push/pull protocol flow. Generated Go code in sgardpb/. Added Makefile proto target, gRPC + protobuf + x/crypto deps, protoc tools to flake devShell. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
