signer param in prepareSendTransaction is misleading

[ElasticBottle]

If we look at @wagmi/core, the prepareSendTransaction takes in a signer which allows for overriding the underlying signer. That is perfect for my use case, but the signer being passed in is only ever being used to estimate the gas.

Later, in sendTransaction, there is not longer a signer option and we fall back to calling fetchSigner.

Is this intended? Feels like an incomplete follow-through with the signer override. What was the original reason for allowing signer in prepareSendTransaction?

Happy to pick this up and contribute the signer override