refactor(rust): Add buffers to zip heads to reduce contention

[orlp]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 18 lines in your changes missing coverage. Please review.

Project coverage is 79.87%. Comparing base (64ca265) to head (9579abb).
Report is 36 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-stream/src/nodes/zip.rs	0.00%	18 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #19036   +/-   ##
=======================================
  Coverage   79.86%   79.87%           
=======================================
  Files        1524     1524           
  Lines      207747   207784   +37     
  Branches     2908     2908           
=======================================
+ Hits       165922   165969   +47     
+ Misses      41276    41266   -10     
  Partials      549      549           

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