Add starknet.rs support

[jelilat]

The RPC Request Builder currently autogenerates starknet.js code snippets for each Starknet RPC endpoint. We need to do the same for starknet.rs.

Ref:

• https://rpc-request-builder.voyager.online/
• https://github.com/xJonathanLEI/starknet-rs

[Prabhat1308]

Hi ! I would like to work on this issue.

[jelilat]

@Prabhat1308 I have broken down the issue into multiple parts. Comment under the one you'd like to start with and I'll assign it to you