Permit3 with 6492 and hooks

[amiecorso]

Exploring the possibility of using ERC-6492 prepareData mechanism to enable the necessary spend preparation steps in simple spend cases for arbitrary smart wallets in a way completely opaque to app devs.

Pros:

• If every wallet supports the generation of 6492 signatures and implements the corresponding utility/hook contract for setting up its onchain smart account, this approach successfully achieves a simple hot path for using Permit3 with any implementation of a smart wallet, completely abstracted from app developers, one-click for users.

Cons:

• more onchain complexity in the implementation of smart account Permit3Utilities
• Not all wallets might implement 6492, and in this case apps still need to set up approvals/ensure funds are available to Permit3, which creates an even worse hot path in this case that also has two branches (6492 v.s. not) than if hooks were used in all cases (without 6492 path)