Add support for parquet ALP encoding

[Kuinox]

Feature Request / Improvement

Hello
The parquet specs recently have put the new encoding, Adaptive Lossless floating-Point (ALP), in preview:
https://github.com/apache/parquet-format/blob/master/Encodings.md#ALP

As of 2026-08-01, this encoding is in Preview.
Note: Preview means that:
The encoding is finalized (the specification is stable).
The implementation is ongoing in the ecosystem (e.g., parquet-java, etc.) but may not be complete.
The Parquet community recommends only using the encoding when you are sure your reader supports it.
Writers are recommended to provide an opt-in flag to enable this encoding.

Would you be open to adding ALP encoding support behind an opt-in?