[Feature Request] Adding a Backend Framework into Eth Scaffold

[auralshin]

I was working towards adding a backend framework into Eth Scaffold to enhance server-side development capabilities, addressing limitations in handling complex off-chain logic and API interactions.
I have created a fork and added a basic Nest js boilerplate with smart contract interactions through ethers js.
If this seems like a good addition, I would create an issue and raise a PR for the same.