feat(python)!: Implement binary serialization of LazyFrame/DataFrame/Expr and set it as the default format

[stinodego]

Closes #17108

Changes

• Add format parameter to the serialize/deserialize methods on DataFrame/LazyFrame/Expr with the options "json" (existing) and "binary" (new).
• Set "binary" as the default format. This is a breaking change. You can retain the previous behavior by specifying format="json"

Example

Before:

>>> lf = pl.LazyFrame({"a": [1, 2, 3]}).sum()
>>> serialized = lf.serialize()
>>> serialized
'{"MapFunction":{"input":{"DataFrameScan":{"df":{"columns":[{"name":...'
>>> from io import StringIO
>>> pl.LazyFrame.deserialize(StringIO(serialized)).collect()
shape: (1, 1)
┌─────┐
│ a   │
│ --- │
│ i64 │
╞═════╡
│ 6   │
└─────┘

After:

>>> lf = pl.LazyFrame({"a": [1, 2, 3]}).sum()
>>> serialized = lf.serialize()
>>> serialized
b'\xa1kMapFunction\xa2einput\xa1mDataFrameScan\xa4bdf...'
>>> from io import BytesIO  # Note: using BytesIO instead of StringIO
>>> pl.LazyFrame.deserialize(BytesIO(serialized)).collect()
shape: (1, 1)
┌─────┐
│ a   │
│ --- │
│ i64 │
╞═════╡
│ 6   │
└─────┘

[stinodego]

ciborium also offers a from_reader_with_buffer which allows finetuning the size of the buffer (default is 4K). I don't really know what size data we're usually looking at, so leaving this at default for now.

[codecov]

Codecov Report

Attention: Patch coverage is 81.71206% with 47 lines in your changes missing coverage. Please review.

Project coverage is 80.84%. Comparing base (4d2f928) to head (86860a3).
Report is 3 commits behind head on main.

Files	Patch %	Lines
py-polars/src/dataframe/serde.rs	59.32%	24 Missing ⚠️
py-polars/polars/dataframe/frame.py	66.66%	4 Missing and 2 partials ⚠️
py-polars/polars/lazyframe/frame.py	64.70%	4 Missing and 2 partials ⚠️
py-polars/polars/_utils/serde.py	89.28%	2 Missing and 1 partial ⚠️
py-polars/polars/expr/expr.py	66.66%	2 Missing and 1 partial ⚠️
py-polars/polars/expr/meta.py	70.00%	2 Missing and 1 partial ⚠️
py-polars/src/expr/serde.rs	98.27%	1 Missing ⚠️
py-polars/src/lazyframe/serde.rs	98.21%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #17223      +/-   ##
==========================================
+ Coverage   80.82%   80.84%   +0.01%     
==========================================
  Files        1466     1470       +4     
  Lines      192313   192381      +68     
  Branches     2745     2750       +5     
==========================================
+ Hits       155446   155538      +92     
+ Misses      36364    36335      -29     
- Partials      503      508       +5     

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