dev: split starknet_ rpc routes in two

[tdelabro]

The Starknet protocol defines a bunch of rpc routes. Madara also need some rpc routes.
Right now, both of those routes are merged under the starknet_ prefix.

I propose we only keep the canonical starknet ones under this prefix, and move all the other custom ones under another prefix. Probably, madara_ in the first time, unless there is a better idea.

[tdelabro]

closed by #1274