Feat: support dual interfaces for all external facing contracts

[sparqet]

Description

External facing smart contracts should implement dual facing interfaces to allow better composability. It means that this contracts should support snake_case and CamelCase at the same time for external functions.

Example on open-zeppelin: OpenZeppelin/cairo-contracts#596

[dbejarano820]

I assume this one will be for later right

[delaaxe]

why is this needed for a brand new protocol on Cairo 2 though?

[zarboq]

It's to facilitate integration of products that already exists for GMX on EVM such as https://twitter.com/Puppetcopy.

But I don't think it's high priority yet. Let's build a working app first 🚀

[tarrencev]

Imo it would be better to handle this on the sdk side. Applications like Puppetcopy would already need a starknet sdk. It can easily abstract this by converting camel case to snake case before constructing the txn