feat: Support reading byte stream split encoded floats and doubles in parquet

[adamreeve]

Fixes #17042

This PR adds support for reading Parquet files with float or double values that are encoded with the byte stream split encoding. I started out using the changes in jorgecarleitao/parquet2#221, but refactored the way the decoder worked to avoid needing to change the State enums for the basic and nested PrimitiveDecoder structs too much (I think these would have at least needed extra type parameters for the ParqueNativeType and converter function).

Version 2.11 of the Parquet format extended the byte stream split encoding to be valid for integer types and fixed length byte arrays, motivated by the addition of the float16 logical type which uses a 2-byte fixed length byte array physical type. But it looks like Polars doesn't support reading float16 data so I think for now it's fine to only handle floats and doubles.

This code doesn't handle when is_filtered is true in build_state, but I couldn't find any code path where that is used by Polars, and is_filtered == true also seems to be unimplemented for dictionary encoded data, so I assume this isn't necessary?

[ritchie46]

Thanks. Looks great. I have left some comments.

[adamreeve]

Thanks for the review, I've addressed those comments and also added a const for the max element size.

[codecov]

Codecov Report

Attention: Patch coverage is 98.67550% with 2 lines in your changes missing coverage. Please review.

Project coverage is 80.89%. Comparing base (8a6bf4b) to head (c95231c).
Report is 28 commits behind head on main.

Files	Patch %	Lines
...uet/src/arrow/read/deserialize/primitive/nested.rs	90.47%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #17099      +/-   ##
==========================================
+ Coverage   80.86%   80.89%   +0.03%     
==========================================
  Files        1456     1458       +2     
  Lines      191141   191484     +343     
  Branches     2728     2742      +14     
==========================================
+ Hits       154562   154902     +340     
  Misses      36073    36073              
- Partials      506      509       +3     

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[ritchie46]

Alright. Thank you @adamreeve