Rust API for editing metadata when creating Parquet and IPC/Arrow output

[thinkingfish]

Description

Currently there doesn't seem to be a way to add or modify metadata (as key-val map) either at the file or column level when exporting dataframe/series to parquet/arrow formats. This could be useful for preserving data lineage and key attributes during data transformation, as Polars gets used as part of a much more extensive data pipeline.

[ritchie46]

Yeap, would accept a PR on this.

[deanm0000]

Are we talking about doing this with polars natively?