The previous commit taught the reconciler to let go of shards an agent says
it is not running. It made no difference on the cluster, because the service
returned early when the agent's list was empty — which is precisely the case
that carries the news.
So the fix was dead code in production while its unit tests passed, and they
passed because they called the reconciler directly. The test added here goes
through the real stream instead, and asserts only that an agent running
nothing reaches the reconciler at all.
That is the lesson worth keeping: a test that calls the function under test
directly cannot tell you the caller never calls it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
