refactor: reorganize and add typing to pint/pint_eval.py

[hgrecco]

• Closes # (insert issue number)
• Executed pre-commit run --all-files with no errors
• The change is fully covered by automated unit tests
• Documented in docs/ as appropriate
• Added an entry to the CHANGES file

[codspeed-hq]

CodSpeed Performance Report

Merging #2134 will not alter performance

_{Comparing develop (f05be7d) with master (2e04c4c)}

Summary

✅ 442 untouched benchmarks
🆕 5 new benchmarks
⁉️ 5 dropped benchmarks

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

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⁉️	test_pint_eval[1 + 2 + 5-_plain_tokenizer]	149.2 µs	N/A	N/A
🆕	test_pint_eval[1 + 2 + 5-plain_tokenizer]	N/A	149.6 µs	N/A
⁉️	test_pint_eval[1-_plain_tokenizer]	136.9 µs	N/A	N/A
🆕	test_pint_eval[1-plain_tokenizer]	N/A	140 µs	N/A
⁉️	test_pint_eval[10 m-_plain_tokenizer]	133.6 µs	N/A	N/A
🆕	test_pint_eval[10 m-plain_tokenizer]	N/A	134.4 µs	N/A
⁉️	test_pint_eval[10 metros * (5 segundos)-_plain_tokenizer]	157.5 µs	N/A	N/A
🆕	test_pint_eval[10 metros * (5 segundos)-plain_tokenizer]	N/A	158.5 µs	N/A
⁉️	test_pint_eval[10 metros + 5 segundos-_plain_tokenizer]	148.6 µs	N/A	N/A
🆕	test_pint_eval[10 metros + 5 segundos-plain_tokenizer]	N/A	149 µs	N/A