feat: Support array arithmetic for equally sized shapes

[ritchie46]

Later we can add trivial broadcasting with literals. Other broadcasting operations require more effort.

[codecov]

Codecov Report

Attention: Patch coverage is 83.33333% with 18 lines in your changes missing coverage. Please review.

Project coverage is 81.34%. Comparing base (4d35be2) to head (d11e417).
Report is 8 commits behind head on main.

Files	Patch %	Lines
crates/polars-core/src/series/series_trait.rs	14.28%	6 Missing ⚠️
...ates/polars-core/src/series/arithmetic/borrowed.rs	88.37%	5 Missing ⚠️
...es/polars-core/src/series/implementations/array.rs	80.00%	3 Missing ⚠️
crates/polars-core/src/series/mod.rs	0.00%	3 Missing ⚠️
crates/polars-core/src/datatypes/dtype.rs	85.71%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16791      +/-   ##
==========================================
+ Coverage   81.29%   81.34%   +0.04%     
==========================================
  Files        1424     1424              
  Lines      187205   187264      +59     
  Branches     2714     2698      -16     
==========================================
+ Hits       152194   152327     +133     
+ Misses      34514    34441      -73     
+ Partials      497      496       -1     

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