Feat: Change Native ERC20 Denom Format to Ensure IBC v2 Compatibility

[zsystm]

Problem

The current denom format for Native ERC20 tokens includes a /, which prevents their transfer via IBC v2.

Closing criteria

Update the Native ERC20 denom format to exclude / and ensure compatibility with IBC v2 for seamless token transfers.

Problem details

• The denom for Native ERC20 tokens is currently stored in the bank module in the format erc20/0x...{contractAddr} (proposal.go#L42-L45)
• In IBC v1, there was no validation logic restricting this format, allowing native ERC20 coins managed in the bank state to be sent and received via IBC.
• Starting with IBC v2, coins with a denom containing / are no longer transferable due to updated validation rules (ibc_module.go#L71-L73).
• This change breaks compatibility for transferring Native ERC20 tokens over IBC, requiring a revision of the denom format to remove the / character and restore functionality.