/**
 * [WHO]: Worker entry for SubprocessSubAgentBackend
 * [FROM]: Depends on node:worker_threads
 * [TO]: Spawned by SubprocessSubAgentBackend
 * [HERE]: core/sub-agent/subprocess-worker.ts
 *
 * Minimal isolated worker. Receives a `WorkerSpec` via workerData, runs
 * a trivial echo loop, and posts a `result` message back. This is the
 * harness that proves the channel + abort + lifecycle wiring; full agent
 * execution inside the worker is intentionally deferred (see backend doc).
 */
export {};