fix: Make replace and replace_strict properly elementwise

[coastalwhite]

Related to #22149.

[codecov]

Codecov Report

Attention: Patch coverage is 93.39623% with 7 lines in your changes missing coverage. Please review.

Project coverage is 80.98%. Comparing base (4903348) to head (7f2481b).
Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-ops/src/series/ops/replace.rs	87.71%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #22465      +/-   ##
==========================================
- Coverage   80.98%   80.98%   -0.01%     
==========================================
  Files        1643     1643              
  Lines      232063   232187     +124     
  Branches     2720     2720              
==========================================
+ Hits       187947   188032      +85     
- Misses      43473    43513      +40     
+ Partials      643      642       -1     

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