ux: Add GET behavior to the Ethereum JSON-RPC endpoint so that it returns information instead of a 404

[Unique-Divine]

Problem

When someone visits an endpoint for Nibiru's Ethereum JSON-RPC, it returns a 404 if visited directly or curl-ed.

Instead, the default view should return some text, so that it's more clear that the page visited is a valid RPC URL.

[Unique-Divine]

Notes from 2024-11-06

• Want link to info on various RPCs
• Info on which chain you're interacting with

You are on testnet-1 evm rpc endpoint.
Chain ID is 69990
You can query it by

 curl https://evm-rpc.testnet-1.nibiru.fi \
  -X POST \
  -H "Content-Type: application/json" \
  --data '{"method":"eth_chainId","params":[],"id":1,"jsonrpc":"2.0"}