Upgrade to Rust 1.81

[MichaReiser]

Summary

Upgrades to Rust 1.81.

I'm a bit worried about the change that an incorrect Ord implementation now panics when sorting instead of resulting in a messed-up sorting. We discovered at least one such bug thanks to fuzzing.

Test Plan

cargo test

[codspeed-hq]

CodSpeed Performance Report

Merging #13265 will degrade performances by 5.13%

_{Comparing micha/rust-1.81 (e74aea7) with main (a4ebe7d)}

Summary

❌ 1 regressions
✅ 31 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	micha/rust-1.81	Change
❌	linter/default-rules[pydantic/types.py]	1.8 ms	1.9 ms	-5.13%

[dhruvmanila]

I'm a bit worried about the change that an incorrect Ord implementation now panics when sorting instead of resulting in a messed-up sorting. We discovered at least one such bug thanks to fuzzing.

Curious to know which bug is this, not sure I see any changes in this PR that's relevant.

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

Formatter (stable)

✅ ecosystem check detected no format changes.

Formatter (preview)

✅ ecosystem check detected no format changes.

[MichaReiser]

It's #12471