Preflight compression can run synchronously before the first model call when a loaded session exceeds the active context threshold. Gateway users saw no visible progress while the compression LLM call was in flight, which can look like a dropped message during long compactions.\n\nEmit the existing lifecycle status through _emit_status before starting preflight compression so CLI, gateway, and WebUI status callbacks all get immediate feedback.\n\nAdds a regression assertion for the preflight path.