Sign Typed Data v3
signTypedData_v3 currently represents the latest version of the EIP 712 spec, making it the most secure method for signing cheap-to-verify data on-chain that we have yet.
This does not mean it is perfect, and does not mean we will not eventually have a
v4, but we do intend to protect this namespace and keep it compatible going forwards.
Hopefully soon we will also have good examples for parsing method input into structs for verification on-chain (great contribution opportunity!)