form to propose adding an interchain asset to vbank

[dckc]

Much like #15, provide a form that makes a core-eval proposal to

1. start a mintHolder instance, given name and decimal places from the form
2. register the resulting issuer with the vbank, given an IBC denom from the form

That is: to call publishInterchainAssetFromBank

also:

• [ ] publish displayInfo under boardAux

Stretch goal:

• [ ] provide a drop-down of IBC denoms, showing channel and remote denom, based on a supply query (distinguish those that are already in the vbank)

background:

• https://github.com/agoric-labs/ag-power-tools/pull/6#issuecomment-1872583086
• add-stATOM.js