- Fix runTcpServer to run the already-wired Server (raftNode was assigned
on a different instance that never accepted clients).
- Cap raft peer connect at 200ms and fan out heartbeats in parallel so a
dead peer cannot stall AppendEntries to the live majority.
- Add raft_writes_e2e_test: 3-node write replication, follower rejection,
and post-failover writes; wire into nimble test + gitignore.
