orchestration: example with custom protobuf messages

[0xpatrickdev]

What is the Problem Being Solved?

As a contract developer, I'd like to use custom protobuf messages in my orchestration contract/flows. I am interested in using something like /osmosis.gamm.v1beta1.MsgJoinPool, a message supported by the Osmosis' ICA implementation, but not yet part of the Orchestration API as osmoAccount.joinPool(..) via OsmosisAccountMethods.

I see a path for this via a test like this that uses executeEncodedTx:

agoric-sdk/packages/orchestration/test/cosmos-interchain-service.test.ts

Lines 168 to 176 in 89bae79

	const delegateMsg = Any.toJSON(
	MsgDelegate.toProtoMsg({
	delegatorAddress: 'cosmos1test',
	validatorAddress: 'cosmosvaloper1test',
	amount: { denom: 'uatom', amount: '10' },
	}),
	);
	const delegateResp = await E(account).executeEncodedTx([delegateMsg]);

But it's less clear how I can go from a .proto file to MsgJoinPool.toProtoMsg() that I can use in an agoric contact. I also see that agoric-sdk has custom configurations for telescope, and I would like to be able to easily leverage these in my dapp-* repo.

Description of the Design

There seem to be two elements to this task:

1. agoric-sdk should provide helpers (or docs?) so it's easy for a dapp developers to transpile proto messages into JS that is compliant with SwingSet / Endo.
2. An example contract that uses executeEncodedTx with a custom proto message.

Security Considerations

Scaling Considerations

Test Plan

Upgrade Considerations