5 endpoints: - GET /api/v1/fleet/hosts — list registered hosts - POST /api/v1/fleet/hosts — register host (name, hostname, apiKey, tags) - DELETE /api/v1/fleet/hosts/:hostId — deregister - GET /api/v1/fleet/status — fleet-wide health check (parallel probes) - POST /api/v1/fleet/deploy — generate multi-host deployment plan Host state persisted in fleet-hosts.json. API keys stored as SHA-256 hashes. Status endpoint probes each host's /api/v1/system/health in parallel with 3s timeout. THIS COMPLETES THE ENTIRE 46-ITEM BACKLOG! 1633 tests pass.