Prop 242: Set up IXO IBC Auto-Forwarding

This proposal, if accepted, would establish the bech32 address prefix 'ixo' as an IBC Auto-Forwarding prefix for SendToCosmos transactions. Any SendToCosmos transactions whose CosmosReceiver field begins with 'ixo' would automatically be forwarded to Impact Hub over IBC channel channel-28. Failed IBC transactions will result in tokens transferred to the equivalent address on the Gravity Bridge chain, requiring the user to import the same seed phrase on Gravity Bridge to rescue funds. When evaluating this proposal the community should be confident that channel-28 is the official channel leading to Impact Hub, and that 'ixo' is the correct prefix for Impact Hub account addresses. For more about IXO and the Impact Hub see https://linktr.ee/ixo_world.