ReadonlysafeBest-effort API shutdown that never throws.
ReadonlyhandleHandles an unrecoverable error: logs it, notifies, and exits 1.
ReadonlyhandleHandles a pipeline-level failure (non-throw): notifies and exits 1.
ReadonlyshutdownGracefully shuts down the API during process termination.
Frozen handle of the four process-lifecycle functions consumed by src/Index.ts and the future ImporterBootstrap.