Convert add-chain.sh into a go package

[bitwiseguy]

Description

This PR converts most of the existing add-chain.sh shell script code into go. As the add-chain.sh shell script grows more complex, it requires us to cover more edge cases and complex conditional statements/branching logic. Golang has the following advantages compared to shell scripting:

• better suited to handle complex logic
• easier to write unit/e2e tests
• easier to modularize
• provides type safety

Tests

An end-to-end test has been added at add-chain/e2e_test.go.

Additional context

This aims to be backwards compatible with the existing documentation in CONTRIBUTING.md that instructs the user to execute sh ./scripts/add-chain.sh standard. Therefore, no documentation changes need to be made as a result of this work.

The add-chain.sh script becomes a wrapper that invokes two go programs:

• [1] superchain-registry/add-chain
• [2] optimism/op-chain-ops/cmd/registry-data

Follow-up work could include moving [2] from the optimism monorepo into a new directory within the superchain-registry repo: superchain-registry/registry-data. This would require removing some light dependencies that program currently has on op-service utility functions, but it would allow all of the scripts/programs related to adding a chain to the superchain-registry to live in the superchain-registry repo.

Metadata

• Fixes bug: fix error handling in add-chain.sh #177
• Fixes Improve hardfork timestamp override handling in add-chain.sh #166

[bitwiseguy]

@geoknee regarding your test failure : I'm hoping this commit will fix it because I believe the smart contract function name is case sensitive. Let me know if it helps.

[geoknee]

@geoknee regarding your test failure : I'm hoping this commit will fix it because I believe the smart contract function name is case sensitive. Let me know if it helps.

This ended up being a problem with my local setup. I fixed that and the script worked!

[geoknee]

Looks like tests failed at least once because of rate limiting. To combat that we could follow this pattern:

superchain-registry/validation/l2oo_test.go

Lines 101 to 104 in 1e360a8

	params.SubmissionInterval, err = retry.Do(ctx, maxAttempts, retry.Exponential(),
	func() (*big.Int, error) {
	return l2OO.SubmissionInterval(callOpts)
	})

[geoknee]

This looks good to me but left quite a few comments.