[processor/processorhelper] Split into separate module

[mx-psi]

Description

Split processorhelper into a separate module. Similar to #12512 in motivation and shape

Link to tracking issue

Fixes #12678

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.52%. Comparing base (562aedc) to head (cb9196c).
Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #12695      +/-   ##
==========================================
- Coverage   91.57%   91.52%   -0.05%     
==========================================
  Files         483      483              
  Lines       26381    26433      +52     
==========================================
+ Hits        24158    24194      +36     
- Misses       1762     1773      +11     
- Partials      461      466       +5     

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