autodetection of constructor arguments

[ayrat555]

resolves #2338

Changlelog:

• add autodetection of constructor arguments

[coveralls]

Pull Request Test Coverage Report for Build 8f73d800-ee1d-43bf-bb9c-1b90dc01e448

• 27 of 33 (81.82%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.05%) to 75.096%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
apps/explorer/lib/explorer/smart_contract/verifier/constructor_arguments.ex	20	26	76.92%

Totals
Change from base Build adfacdd1-46cb-40e3-8b82-22a1ac534ec5:	0.05%
Covered Lines:	5259
Relevant Lines:	7003

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💛 - Coveralls

[vbaranov]

@ayrat555

I thought that Blockscout will show constructor arguments if it is chosen to retrieve them automatically. Anyway, UX suffers a little bit, imho.

Request for changes:

1. If a user chooses to fetch contructor arguments automatically, the field ABI-encoded Constructor Arguments ... should be disabled
2. otherwise, it should be enabled
   3.a. the best option would be to fetch and show constructor arguments immediately on enabling of automatic fetching
   3.b. if you do not choose to retrieve them immediately for some reasons, I'd suggest to completely hide/show the field ABI-encoded Constructor Arguments ... when a user enables/disables auto fetching

[ayrat555]

@vbaranov I added hiding of constructor arguments field

[vbaranov]

@ayrat555 I tried to use auto-appending of arguments. It works incorrectly.

I deployed smart-contract to Sokol with on uint constructor argument /address/0x3ee96c3a3a570de90602384d0d18e5cac06bf791/contracts verified it locally with auto-appending flag. The input value for a single constructor argument was 2, the contract was verified, but this is what I see in the Constructor arguments field of verified contract page. Obviously, the value is wrong: