Finalized the package author and copyright metadata.
Import stats::ave() explicitly so package checks do
not report it as an undefined global function.
Added read_marcxml() for faithful in-memory MARCXML
parsing.
Added marcxml_to_parquet() for bounded-memory
conversion of MARCXML collections to Parquet datasets.
Added optional local parallel parsing through
future.mirai, futurize, and
mori.
Made sequential execution the default for both public functions so that parallel process and memory use are always opt-in.
Preserved inherited namespace declarations when serializing prefixed MARCXML records for independent parsing.