Revest VeFXS for Frax Build 2023

This BUIDL builds on the vesting/yield system of veFXS from the Frax Ecosystem, using Revest core technology. The product allows users to deposit FXS into the veFXS vault and receive an FNFT (Financial FNFT) as a record of their deposit (amount, timelock, and even yield calculated in real-time). Users can deposit additional amounts, extend their locking time, and claim yield natively from their FNFTs. As the veFXS balance is attached to the FNFT's smart wallet address, users are able to sell or lend their veFXS positions to others.