♻️ Encode the challenge in base64 on-chain

[qd-qd]

You may probably ask why we encode the challenge in base64 on-chain instead of of sending it already encoded to save some gas. This library is opinionated and assumes that it is used in the context of Account Abstraction. In this context, valuable information required to proceed with the transaction correctly will be stored in the challenge field meaning we need the challenge in clear to use later in the flow. That's why we decided to encode it here.

[github-actions]

Changes to gas cost

Generated at commit: 7ecb7708f06632f8b6e0a31f75ba9242eee976c5, compared to commit: 274550095ec0b0ea3d9495409e087082dc0bcb23

🧾 Summary (20% most significant diffs)

Contract	Method	Avg (+/-)	%
WebAuthnImplementation	generateMessage verify	+2,137 ❌ +2,138 ❌	+69.47% +0.78%

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Full diff report 👇

Contract	Deployment Cost (+/-)	Method	Min (+/-)	%	Avg (+/-)	%	Median (+/-)	%	Max (+/-)	%	# Calls (+/-)
WebAuthnImplementation	1,114,960 (+64,066)	generateMessage verify	5,213 (+2,137) 277,910 (+2,138)	+69.47% +0.78%	5,213 (+2,137) 277,910 (+2,138)	+69.47% +0.78%	5,213 (+2,137) 277,910 (+2,138)	+69.47% +0.78%	5,213 (+2,137) 277,910 (+2,138)	+69.47% +0.78%	1 (0) 1 (0)