feat: add listcontracts endpoint

[zachdaniel]

The first part of #1569

This adds an rpc endpoint to list contracts according to the spec on that issue. We will probably want to leave this open until #1596 is merged, so that I can add those filters to this PR

Changelog

Enhancements

• Adds a listcontracts action to the contracts rpc endpoint. See the attached issue for more information
• Adds a field Address to the contract model, to support the list endpoint.
• Modularize some of the pagination code so that you can set one of the pagination parameters without having to set both.

[coveralls]

Pull Request Test Coverage Report for Build 650c2e71-7717-4778-b171-ee1718c2e0cd

• 56 of 68 (82.35%) changed or added relevant lines in 6 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.09%) to 83.223%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/contract_controller.ex	19	20	95.0%
apps/explorer/lib/explorer/chain/smart_contract.ex	0	1	0.0%
apps/explorer/lib/explorer/chain.ex	0	10	0.0%

Totals
Change from base Build fa78c39f-3560-4dee-ae87-834dbc4dd4c2:	0.09%
Covered Lines:	4390
Relevant Lines:	5275

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💛 - Coveralls

[ayrat555]

I can't understand this example. error with status code 200?

[zachdaniel]

Honestly, this is just the error description that everything uses. I don't know why, but it returns a 200 code but its an error everywhere in the rpc :(

[vbaranov]

@zachdaniel Could you please add a screenshot of how will API endpoint look on the APIs page? And please update CHNAGELOG.md

[zachdaniel]

[vbaranov]

@zachdaniel #1596 has been merged

[vbaranov]

@zachdaniel

I've tried it locally with Sokol. I've found some bugs. I don't know, would you continue to fix them in this PR or you will do this in a separate one where you will implement #1569 (comment). Please, let me know. The list of the bugs is below:

1. I think we could extend the output data model with the decompiler version.
2. &filter=unverified or &filter=not_decompiled - Not only smart-contracts are returned, but also simple address without contact code. I suppose we should return only smart-contracts for all filters in this endpoint

[vbaranov]

@zachdaniel in addition, If I choose incorrect filter (which is unlisted) it returns me all addresses instead of returning of empty list

[zachdaniel]

The pattern in the RPC that I could see was to ignore parameters that were invalid (not my preferred way of doing it, just what was being done before. I would be fine with returning an error response instead of just returning all results, but I wouldn't want to return an empty list. Also, yeah this should definitely only have addresses with contract_code. I'll fix these and add tests for them.