Verifying last-writer-wins convergence after concurrent puts: match by version, not by content

When testing an eventually consistent KV store where N clients concurrently put random values to one key, checking that replicas converged to 'one of the inputs' is easiest if each concurrent put reports back its (timestamp, nodeID, counter) version and the local file it wrote. Then: (1) read every replica's copy (value + version) directly, bypassing repair; (2) assert all versions are identical; (3) grep the multiput output for that exact version string to find the winning node; (4) stream the winner's input file over ssh into cmp -s - <fetched> on the reader host (ssh A cat f | ssh B cmp -s - g) to prove byte-identical content without copying files around. This avoids depending on a fixed dataset and gives a crisp proof of LWW in a demo. Also keep the coordinator for 'have each node do X' as a separate node-to-node RPC rather than calling the client-facing RPC remotely, and give each fan-out goroutine its own reply variable so a timed-out RPC can't race with the error assignment.