failed PSM trade prevents further service due to inconsistent seat staging

[dckc]

Describe the bug

After accidentally trying to buy AUSD whent he PSM had none, attempts to trade 20 IST for USDC result in a refund rather than a trade.

To Reproduce

In agoricollinet-22, check wallet balances and then attempt to trade 20 IST for USDC:

$ psm-tool --net ollinet --wallet $addr
{
  "balances": [
    [null,"zoe invite"],
    [1.99747,"AUSD"],
    [0,"BLD"],
    [46.800225,"IST"]
  ],
...
}

$ psm-tool --giveStable 20 --boardId $psmInstance --feePct 0.05 >,give20.json
$ agd --from=k1 tx swingset wallet-action --allow-spend "$(cat ,give20.json)"  --node https://ollinet.rpc.agoric.net:443 --chain-id agoricollinet-22 -y
code: 0
...
txhash: 07A7B0CCCD655F0EF2F8ED566380E23D23D6D665B0308671346A250880C6F3FF

Note that 20 IST is withdrawn for this trade:

$ psm-tool --net ollinet --wallet $addr
{
  "balances": [
    [null,"zoe invite"],
    [1.99747,"AUSD"],
    [0,"BLD"],
    [26.800225,"IST"]
  ],
  "offers": [
    ["2022-08-31T14:25:13.203Z","pending","psm","giveStable",{"give":{"In":[20,"IST"]},"want":{"Out":[19.990005,"AUSD"]}}]
  ]
}

But then it gets refunded:

$ psm-tool --net ollinet --wallet $addr
{
  "balances": [
    [null,"zoe invite"],
    [1.99747,"AUSD"],
    [0,"BLD"],
    [46.800225,"IST"]
  ],
  "offers": [
    ["2022-08-31T14:25:13.203Z","accept","psm","giveStable",{"give":{"In":[20,"IST"]},"want":{"Out":[19.990005,"AUSD"]}}]
  ]
}

Use metrics to check PSM pool balance:

$ agoric follow -B https://ollinet.agoric.net/network-config :published.psm.IST.AUSD.metrics
{
  anchorPoolBalance: {
    brand: slot(0,"Alleged: AUSD brand"),
    value: 23002530n,
  },
  feePoolBalance: {
    brand: slot(1,"Alleged: IST brand"),
    value: 2305n,
  },
  totalAnchorProvided: {
    brand: slot(0),
    value: 0n,
  },
  totalStableProvided: {
    brand: slot(1),
    value: 23002530n,
  },
}

Expected behavior

Take my money! And give me USDC in return :)

Platform Environment

ollinet, which is running 1af6550

cc @turadg @dtribble

blocking #6064

[dckc]

Transaction Details

Since these details go away when we restart ollinet:

https://ollinet.explorer.agoric.net/agoric/tx/07A7B0CCCD655F0EF2F8ED566380E23D23D6D665B0308671346A250880C6F3FF

timestamp | 2022-08-31 09:25

property	value
@type	/agoric.swingset.MsgWalletSpendAction
Owner	agoric12x5xgl573q89x6mpx3pz8h4a2m0nw4cl8lhv6h
Spend_action	{ "type": "acceptOffer", "data": { "id": "1661955913203", "instancePetname": "instance@board05311", "requestContext": { "dappOrigin": "unknown", "origin": "unknown" }, "meta": { "id": "1661955913203", "creationStamp": 1661955913203 }, "status": "proposed", "invitationMaker": { "method": "makeGiveStableInvitation" }, "instanceHandleBoardId": "board05311", "proposalTemplate": { "give": { "In": { "pursePetname": "Agoric stable local currency", "value": 20000000 } }, "want": { "Out": { "pursePetname": "AUSD", "value": 19990005 } } } } }