Api for moonbeam integration

[yrong]

Resolves: https://linear.app/snowfork/issue/SNO-1265
Just a thin wrapper on top of Moonbeam's xcm precompile

[alistair-singh]

I am happy with these changes. Great work. However maybe we can support this transfer with a simple Ethers.js abi interface instead of a separate package.

https://docs.ethers.org/v6/getting-started/#starting-contracts

abi = [
  "function decimals() view returns (string)",
  "function symbol() view returns (string)",
  "function balanceOf(address addr) view returns (uint)"
]

// Create a contract
contract = new Contract("dai.tokens.ethers.eth", abi, provider)

This means that moonbeam can just be a module in the existing API package.

[yrong]

Support this transfer with a simple Ethers.js abi interface

Does that imply you prefer to add another high-level precompile on top of the original one into Moombeam's code base?

[alistair-singh]

Support this transfer with a simple Ethers.js abi interface

Does that imply you prefer to add another high-level precompile on top of the original one into Moombeam's code base?

Can we simply use untyped bindings like so?

let abi = [
  "transferAssetsUsingTypeAndThenAddress((uint8,bytes[]),(address,uint256)[],uint8,uint8,uint8,bytes)",
]
const xcmInterfacePrecompile = "0x000000000000000000000000000000000000081A"
let contract = new Contract(xcmInterfacePrecompile, abi, provider)

const tx = await contract[
        "transferAssetsUsingTypeAndThenAddress((uint8,bytes[]),(address,uint256)[],uint8,uint8,uint8,bytes)"
    ](dest, assets, assetTransferType, remoteFeesIdIndex, feesTransferType, customXcmOnDest)

[yrong]

@alistair-singh Move the api into the existing API package in
9cbcf5e