fix: replace source hash should be order independent

[SyMind]

This PR refactors the ReplaceSource replacement ordering logic to make it order-independent. The PR removes the Ord and PartialOrd trait implementations from the Replacement struct and replaces them with a custom comparison function and an optimized binary search algorithm.

• Custom comparison function (compare_replacement_order) replaces trait-based ordering
• Custom binary search implementation (find_insert_index) for better performance with predictable branch patterns
• Manual trait implementations for Hash, PartialEq, and Eq that exclude insertion_order to ensure deterministic hashing
• New test verifying order-independence of replacements

[codspeed-hq]

CodSpeed Performance Report

Merging #195 will not alter performance

_{Comparing fix-replacement (4d1a46c) with main (c4f7e16)}

Summary

✅ 11 untouched
⏩ 5 skipped¹

Footnotes

1. 5 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull Request Overview

This PR refactors the ReplaceSource replacement ordering logic to make it order-independent. The PR removes the Ord and PartialOrd trait implementations from the Replacement struct and replaces them with a custom comparison function and an optimized binary search algorithm.

• Custom comparison function (compare_replacement_order) replaces trait-based ordering
• Custom binary search implementation (find_insert_index) for better performance with predictable branch patterns
• Manual trait implementations for Hash, PartialEq, and Eq that exclude insertion_order to ensure deterministic hashing
• New test verifying order-independence of replacements

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/source.rs	Adds PartialEq and Eq derives to SourceValue enum
src/replace_source.rs	Refactors replacement ordering logic, removes Ord/PartialOrd traits, adds custom binary search, manual trait implementations, and new test for order-independence
Cargo.toml	Adds rand = "0.9.2" as dev-dependency for testing
Cargo.lock	Updates lock file with rand 0.9.2 and its dependencies

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