feat(monad): add monad mainnet

[0xfourzerofour]

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)
• Do your commits follow the Conventional Commits standard?
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PR-Codex overview

This PR introduces the monadMainnet chain configuration to the project, including its details such as ID, name, native currency, RPC URLs, and block explorer.

Detailed summary

• Added monadMainnet chain definition in account-kit/infra/src/chains.ts.
• Defined properties for monadMainnet:
  • id: 143
  • name: "Monad Mainnet"
  • nativeCurrency: { name: "Monad", symbol: "MON", decimals: 18 }
  • rpcUrls: includes default, public, and alchemy URLs
  • blockExplorers: includes a default block explorer
  • testnet: false
• Updated account-kit/infra/src/exports/index.ts to export monadMainnet.

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[cryptozodd]

Interesting

[Chapokill]

Gmonad