Contract verification plugin

This PR adds a generalized contract verification plugin. Contracts written / compiled in Remix can be verified at Sourcify, Etherscan and Blockscout at the same time. It basically adds all the features the separate Etherscan and Sourcify plugins had and makes them obsolete.

Features:

Verify contracts and their proxies on Sourcify, Etherscan and Blockscout by providing the source code to their APIs
Check the verification status via receipts that are stored in local storage
Lookup up the source code of any address and add it to Remix, if the respective contract is verified on one of the three verifiers

The plugin isn't enabled by default yet, as I wasn't sure how to do it.

We had to make changes to the compiler-artefacts.ts to be able to get the compiler input JSON of contracts. Some more info about this here: https://github.com/sourcifyeth/remix-project/pull/1

ethereum / remix-project

Contract verification plugin #5221

Deploy request for remixproject pending review.

ethereum / remix-project

Contract verification plugin #5221

👷 Deploy request for remixproject pending review.

Deploy request for remixproject pending review.