Permit2 in place of Allow

[0x4007]

Gasless generalized approvals for token transfers seem like far better UX vs approvals. We should consider looking into adding this to our protocol.

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Tired: Hanging token approvals 🔓
Wired: Expiring token approvals 🔒

Permit2 is live on Uniswap! So what?

🦄 Uniswap Labs: Every time we upgrade our router, users have to spend gas to re-approve tokens. But no more!

With Permit2, you'll need to re-approve now, but never again. Spend small for big savings later!

💻 Devs: Permit2 is open source! You can integrate it for:

🤝 Shared approval management across applications
☝️ Universal permits for any token
⏰ Time-bound token approvals
🧺 Batch approvals & revokes for tokens

🔁 Users: Approving max token balances forever is a security risk. With Permit2, token approvals expire every 30 days and can be reauthorized with a gasless signature.

https://uniswap.org/blog/permit2-and-universal-router

https://twitter.com/uniswap/status/1615824670825250816?s=46&t=K_CSWLEw5j2pu48fWneUqw