feat: Ensure unique names in HConcat

[ritchie46]

fixes #17862

[codecov]

Codecov Report

Attention: Patch coverage is 93.75000% with 1 line in your changes missing coverage. Please review.

Project coverage is 80.57%. Comparing base (55c15d7) to head (6fbce8f).
Report is 1 commits behind head on main.

Files	Patch %	Lines
crates/polars-stream/src/nodes/zip.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #17884   +/-   ##
=======================================
  Coverage   80.56%   80.57%           
=======================================
  Files        1495     1495           
  Lines      197009   197006    -3     
  Branches     2813     2813           
=======================================
+ Hits       158720   158733   +13     
+ Misses      37768    37752   -16     
  Partials      521      521           

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