chore: reduction close copied tool output stream

[N3kox]

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[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (alpha/09@664af32). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
adk/middlewares/reduction/reduction.go	50.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             alpha/09    #1008   +/-   ##
===========================================
  Coverage            ?   82.95%           
===========================================
  Files               ?      162           
  Lines               ?    22100           
  Branches            ?        0           
===========================================
  Hits                ?    18332           
  Misses              ?     2536           
  Partials            ?     1232           

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