depr(python): Deprecate allow_missing_columns in scan_parquet in favor of missing_columns

[nameexhaustion]

• ref Remove allow_missing_columns: bool in favor of missing_columns: Literal["insert", "raise"] #21997
• Depends on feat(python): Add extra_columns parameter to scan_parquet #22699

[codecov]

Codecov Report

Attention: Patch coverage is 66.66667% with 8 lines in your changes missing coverage. Please review.

Project coverage is 80.63%. Comparing base (5cec049) to head (e5c6d10).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-python/src/io/mod.rs	69.23%	4 Missing ⚠️
py-polars/polars/io/parquet/functions.py	57.14%	2 Missing and 1 partial ⚠️
crates/polars-io/src/parquet/read/reader.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #22784      +/-   ##
==========================================
- Coverage   80.63%   80.63%   -0.01%     
==========================================
  Files        1677     1677              
  Lines      222209   222226      +17     
  Branches     2801     2803       +2     
==========================================
+ Hits       179178   179190      +12     
- Misses      42364    42367       +3     
- Partials      667      669       +2     

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[nameexhaustion]

Parameter parsing will be done on the Rust-side in PyScanOptions