Create a specification and a base implementation for CW-4626

[aesmonty]

TLDR

The goal is to adapt the EIP-4626 standard for vaults and interest-bearing tokens to CosmWasm

Background

The EIP-4626 (https://eips.ethereum.org/EIPS/eip-4626) is a standard for tokenized vaults, with the goal of increasing composability between DeFi apps, while providing a more secure and standardized interface.

Motivation

Vaults are commonly implemented in a wide range of Defi applications such as lending markets, yields aggregators, etc. These vaults are normally implemented as yield-bearing tokens and should conform with the CW20 as well. Given how widespread their use is, it would be very helpful to adopt a shared interface of this "Defi lego", to improve developer experience, forward compatibility, and security.

Next steps

If this CW standard is deemed to be useful and we agree on a high-level spec, I can bootstrap the efforts and lead the implementation. It'd be great to do this collaboratively, so any help or contributor is more than welcome :)

[Jammyaa]

Hi, I think it is interesting and necessary to bring DeFi smart contract standards to Cosmwasm. So, we should start at CW4626.

[ethanfrey]

I see the purpose of a standard reference for such logic.

cw-plus is defined for a basic set of contracts that are production ready and serve as references for common actions. But is not intended to implement every use case.

We also created the cw-tokens repo for many more extensions and that would be a great place for such a token contract. If you make a PR for an implementation, I am happy to get it reviewed.

[ethanfrey]

Again, I would move this issue to the other repo. Happy to see contributions from the community there