[Feature] Integrate `eth_callMany` support into `EthCall` builder

[zerosnacks]

Component

provider, pubsub, rpc

Describe the feature you would like

Rather than adding eth_callMany as an RPC method it should be integrated into the EthCall builder.

A previous PR proposed adding this to the debug namespace which is incorrect: https://github.com/alloy-rs/alloy/pull/1085

Additional context

No response