The test copies the node-engine's repository from beside the check (MESH_CHECK_BESIDE, mesh-host, with mesh-sdk's Go module beside it as one workspace when a group places it), has the module build github.com/novox/mesh-host/cmd/mesh-compose there, and runs it; it fails loudly when the repository is not beside. Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL