chore: improve fast timers

[Uzlopak]

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• I have read and agreed to the Developer's Certificate of Origin
• Tested
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[Copilot]

Pull Request Overview

This PR improves the performance and reliability of fast timers by replacing the array-based timer management with a binary min-heap data structure and refactoring the timer processing logic.

• Replaces the linear array-based timer storage with an efficient binary min-heap for O(log n) insertion/removal operations
• Separates pending timers from active timers using dedicated data structures to improve processing efficiency
• Adds comprehensive test coverage for edge cases including concurrent timer operations, heap ordering, and timer lifecycle management

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
lib/util/timers.js	Implements TimerHeap class and refactors timer management logic from array-based to heap-based approach
test/timers.js	Adds extensive test coverage for timer edge cases, heap operations, and concurrent timer scenarios

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 99.30070% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.96%. Comparing base (4481850) to head (726defc).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/util/timers.js	99.30%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4593      +/-   ##
==========================================
+ Coverage   92.93%   92.96%   +0.03%     
==========================================
  Files         106      106              
  Lines       33094    33270     +176     
==========================================
+ Hits        30756    30931     +175     
- Misses       2338     2339       +1     

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[gurgunday]

Why not bitwise operators?

Ref: https://github.com/nodejs/node/blob/170848bc1831ea9be665b527e2131c81263dfd2c/lib/internal/priority_queue.js