feat(app): add Mean Finance integration

[FiboApe]

Description

Adds Mean Finance integration with its DCA Positions. Mean Finance is the state-of-the-art DCA open protocol that enables users (or dapps) to Dollar Cost Average (DCA) any ERC20 into any ERC20 with their preferred period frequency, without sacrificing decentralization or giving up personal information to any centralized parties. We do all of this by leveraging both Chainlink and Uniswap V3 TWAP oracles.

More info on our docs

Checklist

• I have followed the Contributing Guidelines
• (optional) As a contributor, my Ethereum address/ENS is: fiboape.eth
• (optional) As a contributor, my Twitter handle is: @FiboApe

How to test?

http://localhost:5001/apps/mean-finance/balances?addresses[]=0x7AfB052ae7B80aAc6e559281cC261089738b66F6&network=polygon
http://localhost:5001/apps/mean-finance/balances?addresses[]=0xf488aaf75D987cC30a84A2c3b6dA72bd17A0a555&network=optimism

Can add more addresses if needed :)

[immasandwich]

Please prefix the contracts in mean-finance/contracts/abis with mean-finance, i.e.: mean-finance-hub.json.

This will make it easier to find files in this repo as it continues to grow!

[immasandwich]

Remove "our". The description should not be from the perspective of the protocol contributor, but rather as a third party. i.e.: "Mean Finance enables users to ..."

[immasandwich]

Overall looks great, but are you able to create contract positions for this protocol? i.e.: is there a contract that serves as the entrypoint for funds into your DCA positions?

If so, its better to have it listed via a ContractPositionFetcher since that will enable us to calculate TVL, determine the number of users in your protocol, etc.

[immasandwich]

OK I see that Mean Finance maintains positions via NFT tokens deposited through the DCA Hub. You can create a ContractPosition representing a deposit to the DCA Hub (https://optimistic.etherscan.io/address/0x059d306a25c4ce8d7437d25743a8b94520536bd5).

You don't need to use this ContractPosition in the balance fetcher, but this will enable Zapper to perform the optimizations mentioned earlier, and also enable us to calculate the TVL of Mean Finance for a neat upcoming feature.

[FiboApe]

@immasandwich thank you for the review! All is up to date now