refactor(orchestration): simplify example guest code (#9586)

closes: #XXXX
refs: https://github.com/Agoric/agoric-sdk/pull/9566/files#r1653602477

## Description

At https://github.com/Agoric/agoric-sdk/pull/9566/files#r1653602477 @dckc commented on a cleanup that I thought I did and marked as done, but was not done. 

Before #9566, the code that would be guest code had several workarounds marked `// XXX when() until membrane` that correctly indicated that they should be cleaned up as of #9566, which introduces exactly that membrane.

In addition, guest code has no need for `heapVowE` since it doesn't see vows. It should just use the normal `E`. To keep this distinct, I stopped renaming `hostVowE` where host code needs it in the same file.

### Security Considerations
none
### Scaling Considerations
none
### Documentation Considerations
examples are now more like what we want to teach
### Testing Considerations
I believe this PR is a pure refactor that should not have any observable effects. Thus, it should not affect any tests. We'll see soon.
### Upgrade Considerations
none

packages/orchestration/src/examples/sendAnywhere.contract.js

@@ -1,7 +1,8 @@
 import { withdrawFromSeat } from '@agoric/zoe/src/contractSupport/zoeHelpers.js';
 import { InvitationShape } from '@agoric/zoe/src/typeGuards.js';
 import { M, mustMatch } from '@endo/patterns';
-import { heapVowE as E } from '@agoric/vow/vat.js';
+import { E } from '@endo/far';
+import { heapVowE } from '@agoric/vow/vat.js';
 import { makeStateRecord } from '@agoric/async-flow';
 import { AmountShape } from '@agoric/ertp';
 import { CosmosChainInfoShape } from '../typeGuards.js';
@@ -53,20 +54,16 @@ const sendItFn = async (
   const { chainName, destAddr } = offerArgs;
   const { give } = seat.getProposal();
   const [[kw, amt]] = entries(give);
-  // XXX when() until membrane
-  const { denom } = await E.when(agoricNamesTools.findBrandInVBank(amt.brand));
+  const { denom } = await agoricNamesTools.findBrandInVBank(amt.brand);
   const chain = await orch.getChain(chainName);
 
-  // FIXME ok to use a heap var crossing the membrane scope this way?
   if (!contractState.account) {
     const agoricChain = await orch.getChain('agoric');
-    // XXX when() until membrane
-    contractState.account = await E.when(agoricChain.makeAccount());
+    contractState.account = await agoricChain.makeAccount();
     console.log('contractState.account', contractState.account);
   }
 
-  // XXX when() until membrane
-  const info = await E.when(chain.getChainInfo());
+  const info = await chain.getChainInfo();
   console.log('info', info);
   const { chainId } = info;
   assert(typeof chainId === 'string', 'bad chainId');
@@ -156,7 +153,9 @@ export const start = async (zcf, privateArgs, baggage) => {
         const chainKey = `${chainInfo.chainId}-${(nonce += 1n)}`;
         // when() because chainHub methods return vows. If this were inside
         // orchestrate() the membrane would wrap/unwrap automatically.
-        const agoricChainInfo = await E.when(chainHub.getChainInfo('agoric'));
+        const agoricChainInfo = await heapVowE.when(
+          chainHub.getChainInfo('agoric'),
+        );
         chainHub.registerChain(chainKey, chainInfo);
         chainHub.registerConnection(
           agoricChainInfo.chainId,

packages/orchestration/src/examples/swapExample.contract.js

@@ -4,7 +4,6 @@ import { withdrawFromSeat } from '@agoric/zoe/src/contractSupport/zoeHelpers.js'
 import { Far } from '@endo/far';
 import { deeplyFulfilled } from '@endo/marshal';
 import { M, objectMap } from '@endo/patterns';
-import { heapVowTools } from '@agoric/vow/vat.js';
 import { orcUtils } from '../utils/orc.js';
 import { provideOrchestration } from '../utils/start-helper.js';
 
@@ -34,10 +33,8 @@ const stackAndSwapFn = async (orch, { zcf }, seat, offerArgs) => {
   const agoric = await orch.getChain('agoric');
 
   const [omniAccount, localAccount] = await Promise.all([
-    // XXX when() until membrane
-    heapVowTools.when(omni.makeAccount()),
-    // XXX when() until membrane
-    heapVowTools.when(agoric.makeAccount()),
+    omni.makeAccount(),
+    agoric.makeAccount(),
   ]);
 
   const omniAddress = omniAccount.getAddress();