feat: LEAP-824: Remove duplicated tasks with moving of annotations

[makseq]

This PR moves previously hidden behind EXPERIMENTAL_FEATURES=1 flag remove_duplicates to public access.
Also it adds slight code refactoring and a new feature: moving annotations to the "first" task among duplicated ones before removing duplicates.

PR fulfills these requirements

• Commit message(s) and PR title follows the format [fix|feat|ci|chore|doc]: TICKET-ID: Short description of change made ex. fix: DEV-XXXX: Removed inconsistent code usage causing intermittent errors
• Tests for the changes have been added/updated (for bug fixes/features)
• Docs have been added/updated (for bug fixes/features)
• Best efforts were made to ensure docs/code are concise and coherent (checked for spelling/grammatical errors, commented out code, debug logs etc.)
• Self-reviewed and ran all changes on a local instance (for bug fixes/features)

Change has impacts in these area(s)

(check all that apply)

• Product design
• Backend (Database)
• Backend (API)
• Frontend

Does this PR introduce a breaking change?

(check only one)

• Yes, and covered entirely by feature flag(s)
• Yes, and covered partially by feature flag(s)
• No
• Not sure (briefly explain the situation below)

What level of testing was included in the change?

(check all that apply)

• e2e
• integration
• unit

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.18%. Comparing base (b08b623) to head (6283c18).
Report is 9 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #5572      +/-   ##
===========================================
+ Coverage    75.79%   76.18%   +0.39%     
===========================================
  Files          157      158       +1     
  Lines        13133    13181      +48     
===========================================
+ Hits          9954    10042      +88     
+ Misses        3179     3139      -40     

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