Add Tether, USDC, and DAI stablecoins

[woodser]

This issue requests adding Tether (USDT), USDC, and DAI stablecoins.

Tether should support ERC20 and TRC20.

Bisq already lists USDT, USDC, and DAI, so the implementation should start with those as a base.

They must be integrated into Haveno's API, so the test "Can validate payment account forms" passes in haveno-ts.

See #987 and #1037 for more discussion.

[emmanuemmanu]

Thank u. If possible also include DAI ERC20 stablecoin on Ethereum chain

[shortwavesurfer2009]

What about polygon chain, etc. Fees on eth can go nuts

[KewbitXMR]

At the moment there is only one ‘type’ of cryptocurrency paymentMethod which has the paymentMethodId of BLOCK_CHAINS, perhaps the best way to implement this would be to add BEP20_CHAIN and ERC20_CHAIN and the popular supported coins as ‘accepted currencies’ that way logic per-chain can be implemented in efforts to make some transactions instant eventually.

[woodser]

I think Tether can be added as just another crypto, and the address validation simply accepts ERC20 and TRC20 addresses.

Still waiting on someone to implement this.

[bvcxza]

https://bounties.monero.social/posts/175/haveno-add-support-for-dai