chore: remove Monad Mainnet single call balance contract and add into account v4

[stanleyyconsensys]

Explanation

This PR does:

• remove Monad Mainnet from SINGLE_CALL_BALANCES_ADDRESS_BY_CHAINID, since Monad Mainnet is not yet launch, and no where is using, so it is not a breaking change
• Add Monad Mainnet into SUPPORTED_NETWORKS_ACCOUNTS_API_V4

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed, highlighting breaking changes as necessary
• I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes

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Note

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