refactor(adk): refactor tool reduction middleware

[N3kox]

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[codecov]

Codecov Report

❌ Patch coverage is 70.17544% with 34 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (alpha/08@788da21). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
adk/middlewares/reduction/reduction.go	72.64%	14 Missing and 15 partials ⚠️
adk/middlewares/reduction/consts.go	37.50%	5 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             alpha/08     #762   +/-   ##
===========================================
  Coverage            ?   79.81%           
===========================================
  Files               ?      146           
  Lines               ?    15790           
  Branches            ?        0           
===========================================
  Hits                ?    12602           
  Misses              ?     2209           
  Partials            ?      979           

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