Refactor NPY201

[AlexWaygood]

Summary

This PR refactors the NPY201 rule to reduce nesting and indentation in the code. It's just a pure refactor; there's no substantive changes here. I'm opening this because it makes it easier to rework the code slightly in order to address #12476. It's a separate PR because it changes the indentation for a very large range of lines, creating a pretty big diff.

Test Plan

cargo test -p ruff_linter --lib

[MichaReiser]

Lol. Exactly the same amount of added and removed lines. I'll take a look tomorrow unless someone else beats me to it

[codspeed-hq]

CodSpeed Performance Report

Merging #12479 will improve performances by 4.26%

_{Comparing alex/refactor-numpy (ef0c7b4) with main (3af6ccb)}

Summary

⚡ 1 improvements
✅ 32 untouched benchmarks

Benchmarks breakdown

	Benchmark	main	alex/refactor-numpy	Change
⚡	lexer[numpy/globals.py]	30.4 µs	29.2 µs	+4.26%

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.