Update Core Bridge Cosmwasm contract to publish IBC Message to wormchain

[nik-suri]

Edit the publishMessage function to send an IBC message to wormchain instead of directly emitting a wormhole message on the source chain.

This functionality should ideally be enabled using a compile-time feature flag.

[jynnantonix]

Unfortunately there's no way to properly do mutually exclusive compile time features in rust in a single crate. Cargo features are supposed to be additive:

A consequence of this is that features should be additive. That is, enabling a feature should not disable functionality, and it should usually be safe to enable any combination of features.

If we want to do this the Right Way (TM) then I think we should have a new "wormhole-ibc" contract that depends on the original core bridge as a library, delegates all the handling to the original core bridge, and then converts any attributes and events from the Response struct into IBC messages that get posted to wormchain.

See the various *-shutdown contracts for examples where we've done something similar.