The Overview dropdown previously rendered "X active · Y running" where
both X (stats.activeCount) and Y (activeAgents.length) counted agents
whose state was either "active" or "running" — so an agent that was
merely enabled but idle would still inflate the "running" tally. The
label now counts each state distinctly so "running" only reflects
agents that are mid-heartbeat. Adds AgentsOverviewBar.test.tsx to lock
in the new contract.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
