Add changeCoinType to @magic-ext/cosmos

[schnetzlerjoe]

✨ Feature Request

It would be amazing for the Cosmos ecosystem if you simply added the ability to change the coin-type like you can change the addressPrefix. This will open Magic Link up to more than 40+ other chains in one go.

🧩 Context

We will use it at mysticlabs.xyz for sure but the entire ecosystem in Cosmos would use it as well.

💻 Examples

If you are using offlineSigner from cosmjs which I am assuming is going on, you just simply make the coin type dynamic. It should not be a major overhaul for a big uplift.