verify coin

[rsoeldner]

see kadena-io/pact#1124 for the reason we need to assert a valid miner in the first step.
Additionally, the conserves-mass property is not applicable in this case (defpact), as it has to be true for all step.

[emilypi]

aha but they can be the same! Just, they should exist on different chains, which we have no means of expressing in the current system.

[rsoeldner]

this property is requested by the transfer-crosschain of the fungible-v2 interface, see https://github.com/kadena-io/chainweb-node/blob/master/pact/coin-contract/v2/fungible-v2.pact#L94

[emilypi]

fungible-v2 has an invalid property then 😞

[emilypi]

As discussed off-band, we'll not want a fungible-v3, but rather we'll want to modify fungible-v2 to replace the offending models with the "correct" ones so that, while on-chain, the old fungible-v2 will remain, but off-chain, people will be able to cargo-cult the fixed interface. Concretely, my proposal is this:

1. fungible-v3 should be renamed to fungible-v2, and replace the current fungible-v2 i the main repo.
2. The on-chain (i.e. old) fungible-v2 should be moved to its own directory, including a note (say, CAVEAT.md), which details the discrepancy and why there are two, plus how to distinguish between them.
3. We scope any potential changes to coin for the next release, which will include more than just what we spoke about. It will include changes such as shutting off account creation for non-principals, and removing rotate.