OptionalconcurrencyMaximum number of concurrent tasks.
map(): Controls how many individual items are processed concurrentlymapBatch(): Controls how many batches are processed concurrentlyOptionalpreserveWhether to preserve the order of results.
When true, results are yielded in the same order as the input items,
which may reduce throughput as processing waits for earlier items to complete.
When false, results are yielded as soon as they're available.
Configuration options for Stream.map operations.