feat: add ark-ff-06

[Robert-MacWha]

Motivation

Solves #583

Solution

PR Checklist

• Added Tests
• Added Documentation
• Updated the changelog

[Robert-MacWha]

Ran tests locally and it seems to be working. If there's any issues in the CI I can fix them

[prestwich]

Thanks, I will review :)

[prestwich]

lgtm — pure clone of ark_ff_05.rs with 05→06 version bumps

[codspeed-hq]

Merging this PR will improve performance by 11.41%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 3 improved benchmarks
✅ 383 untouched benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	most_significant_bits/4096/4096	28.9 µs	26.1 µs	+10.87%
⚡	to/f32/4096	28.7 µs	25.7 µs	+11.33%
⚡	to/f64/4096	28.8 µs	25.8 µs	+11.41%

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_{Comparing Robert-MacWha:main (3dc44f0) with main (836a44f)}