The 0011 chaos test validated only the control plane (healthz + leader
failover + KV readable with 2/3); it never connected an authenticated bus
client to the data plane. cmd/clientcheck is a reusable verification tool: it
connects with a real identity (nkey + TLS on both planes, multi-node seed
lists), creates an ephemeral E2E room (encrypted + signed, no durable stream),
and either publishes N messages and asserts all come back decrypted (golden)
or publishes a counter for a duration while logging the attached node (loop),
so stopping a node mid-run shows the client fail over to a survivor and keep
receiving with quorum 2/3.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
