feat: add http debug options to alchemyTransport

[thebrianchen]

Add viem's http options into alchemyTransport for easier debugging

Pull Request Checklist

• Did you add new tests and confirm existing tests pass? (yarn test)
• Did you update relevant docs? (docs are found in the site folder, and guidelines for updating/adding docs can be found in the contribution guide)
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• Does your PR title also follow the Conventional Commits standard?
• If you have a breaking change, is it correctly reflected in your commit message? (e.g. feat!: breaking change)
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PR-Codex overview

This PR focuses on enhancing the alchemyTransport functionality by adding HTTP debugging options and refining the configuration interface. It updates documentation and tests to reflect these changes, improving usability for developers.

Detailed summary

• Added HTTP debugging options: onFetchRequest and onFetchResponse.
• Introduced timeout parameter in alchemyTransport.
• Updated AlchemyTransportConfig to extend HttpTransportConfig.
• Revised documentation to clarify configuration options.
• Enhanced test coverage for the new debugging features.

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[jakehobbs]

aren't the retry & fetch options part of this HttpTransportConfig too in viem? do you think it's weird that we are picking some of these to be here, but others to be top level? curious to hear your thoughts.