v0.0.5

Everything in v0.0.4, plus the runner's half of the heartbeat: runnerd pings its control socket on an interval and redials when a ping goes unanswered, so a control-plane instance replaced behind a load balancer no longer leaves a runner off the fleet until the kernel's keepalive gives up. The bounds are on AgentConfig (defaults 20 s / 10 s). Found by the hosted cell's first agent-credential live gate. Hosted deployments: republish the runner artifacts from this tag before the next plane raise.