explorer: add support for user operations

[alvrs]

• add client override for sendUserOperation for observer support for user operations:

  mud/packages/explorer/src/observer/decorator.ts

  Line 26 in f06169a

  async writeContract(args) {

• find and decode entry point transactions for user operation support in chain watcher:

const transaction = await getTransaction(userClient, { hash: txHash! });
if (transaction.to === entryPoint07Address) {
  console.log("entry point transaction", transaction);

  const decodedEntryPointCall = decodeFunctionData({
    abi: entryPoint07Abi,
    data: transaction.input,
  });

  const userOps = decodedEntryPointCall.args[0] as PackedUserOperation[];
  console.log("user operations", userOps);

  const decodedSmartAccountCall = decodeFunctionData({
    abi: parseAbi(["function execute(address target, uint256 value, bytes calldata data)"]),
    data: userOps[0].callData,
  });

  console.log("decoded smart account call", decodedSmartAccountCall);
}

Note this snippet only considers entry point 0.7 transactions and only those that use a smart account that has the execute signature. We can add support for more in the future.