feat: injector utility

[eguguchkin]

Fixes #403

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• I have read and followed all requirements in CONTRIBUTING.md;
• I used LLM/AI assistance to make this pull request;

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 63 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.15%. Comparing base (124d460) to head (378ca56).

Files with missing lines	Patch %	Lines
cmd/inserter/main.go	0.00%	63 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #404      +/-   ##
==========================================
- Coverage   71.40%   71.15%   -0.26%     
==========================================
  Files         219      220       +1     
  Lines       16454    16517      +63     
==========================================
+ Hits        11749    11752       +3     
- Misses       3834     3893      +59     
- Partials      871      872       +1     

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