• Asynchronous CSV→JSON with optional worker-thread parallelization.

    • useWorkers: false (default) — synchronous in the calling thread.
    • useWorkers: true, workerCount: N — N workers; 0 = availableParallelism().
    • Worker path activates only when csv.length >= 256KB (overridable).

    Falls back to sync silently if worker_threads is unavailable (browser builds, restricted runtimes) or if a worker errors out.

    Parameters

    Returns Promise<AnyArray>