feat(python): Add allow_copy parameter to DataFrame.to_numpy

[stinodego]

Ref #14334

Changes

• Add allow_copy parameter to DataFrame.to_numpy, which will raise an error if a copy is required to perform the conversion
• For Series.to_numpy, deprecate the zero_copy_only parameter in favor of allow_copy which is the inverse.

[codecov]

Codecov Report

Attention: 18 lines in your changes are missing coverage. Please review.

Comparison is base (f044280) 80.77% compared to head (0094802) 77.89%.
Report is 4 commits behind head on main.

❗ Current head 0094802 differs from pull request most recent head 8886c9f. Consider uploading reports for the commit 8886c9f to get more accurate results

Files	Patch %	Lines
py-polars/polars/series/series.py	0.00%	11 Missing ⚠️
py-polars/polars/dataframe/frame.py	0.00%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14569      +/-   ##
==========================================
- Coverage   80.77%   77.89%   -2.89%     
==========================================
  Files        1326     1326              
  Lines      173035   173045      +10     
  Branches     2439     2441       +2     
==========================================
- Hits       139773   134790    -4983     
- Misses      32791    37812    +5021     
+ Partials      471      443      -28     

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