refactor(poseidon-cipher): simplify nonce validation using Num2Bits

[0x471]

re #16

Description

• Removed the explicit two128 variable declaration (var two128 = 2 ** 128)
• Replaced the nonce validation using LessThan component with a simpler Num2Bits(128)(nonce) check
• Changed ength * two128 to length << 128 in the initial state calculation for better consistency with bit operations

Related Issue(s)

Fixes #16

Other information

Checklist

• I have read and understand the contributor guidelines and code of conduct.
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I have run yarn style without getting any errors
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Important

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