Add Bench for Babybear

[jotabulacios]

Add Bench for Babybear

Description

This PR adds benchmarks for BabyBear field arithmetic operations in both the base field and its degree-4 extension field.

Results for 1 million operations

Operation	Lambdaworsk	Plonky3	Percentage Difference
Addition	610.68 µs	629.35 µs	2.97%
Multiplication	747.44 µs	701.59 µs	-6.53%
Squaring	1.0284 ms	612.02 µs	-68.03%
Division	138.03 ms	84.085 ms	-64.16%
Inversion	139.71 ms	80.817 ms	-72.87%
Addition Fp4	877.75 µs	529.44 µs	-65.79%
Multiplication Fp4	14.218 ms	12.625 ms	-12.62%
Squaring Fp4	10.603 ms	12.177 ms	12.93%
Division Fp4	168.18 ms	188.82 ms	10.93%
Inversion Fp4	193.61 ms	162.75 ms	-18.96%

Checklist

• Benchmarks added/run

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.04%. Comparing base (13fae9c) to head (456c4fa).
Report is 3 commits behind head on baby-bear-extension.

Additional details and impacted files

@@                   Coverage Diff                   @@
##           baby-bear-extension     #947      +/-   ##
=======================================================
- Coverage                71.09%   71.04%   -0.05%     
=======================================================
  Files                      154      154              
  Lines                    33093    33111      +18     
=======================================================
- Hits                     23527    23525       -2     
- Misses                    9566     9586      +20     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.