opts.memo disappears when making E(localOrcAccount).transfer that requires PFM

[anilhelvaci]

Problem Definition

Currently localOrchestrationAccount's transfer method accepts memo through its arguments. This works fine when the packet is sent directly to the destination chain. However, if we have to send a memo to the destination chain the pfm's forward memo takes precedence over what zoe contract is supplying. See;

agoric-sdk/packages/orchestration/src/exos/local-orchestration-account.js

Lines 381 to 384 in e77f936

	if (forwardInfo) {
	// forward memo takes precedence
	memo = JSON.stringify(forwardInfo);
	}

This situation creates a problem in situations like Osmosis' crosschain swaps where we have to have a specific memo attached to the packet in order to trigger the cosmwasm contract on Osmosis.

To Reproduce

Steps to reproduce the behavior, in your orchestration contract;

1. Create a localOrchestationAccount
2. Create an offer handler or address hook where you pass a memo to the transfer. Like;

await localOrchestraitonAccount.transfer(
  {
    value: destAddr,
    encoding: 'bech32',
    chainId: /** @type {CosmosChainInfo} */ (osmosisChainInfo).chainId,
  },
  { denom, value },
  { memo },
);

3. Initiate a transfer where destination chain is not the issuer chain of the token in transfer. For example, send Agoric wrapped ATOM to Osmosis
4. Open the Osmosis logs and see memo isn't in the packet

Expected behavior

We should protect the memo passed in by the application and observe it on the destination chain even with PFM involved.

Possible Solution

Make sure we attach the opts.memo (memo sent by application code) to the pfm's forward.next