fix: file fingerprinting is now ~33% faster

[rix0rrr]

During some recent investigations package fingerprinting was found to do a bunch of duplicate work (mostly statting the same files over and over again).

That and a number of minor tweaks bring the fingerprinting time of one specific directory down from ~19s to ~13s (about ~30% improvement), while maintaining byte-for-byte compatibility with the previous implementation.

In a future change, we will investigate changes that are allowed to change the hash to improve the performance even more.

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Merge Queue Status

• ✅ Entered queue — 2026-05-11 11:01 UTC · Rule: default-squash
• ✅ Checks passed · in-place
• ✅ Merged — 2026-05-11 11:57 UTC · at cd9f7dd2982f766f1c41d81f7f59ede5f7985a12 · squash

This pull request spent 56 minutes 7 seconds in the queue, including 30 minutes 31 seconds running CI.

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  • fix: file fingerprinting is now ~33% faster #37802
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  • fix: file fingerprinting is now ~33% faster #37802
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