Move from to the prepare input, as needed for gas estimation

Signed-off-by: Peter Broadhurst <[email protected]>

pkg/ffcapi/api_common.go

@@ -71,12 +71,12 @@ type Header struct {
 // - The interface is a structure describing the method to invoke. The `variant` in the header tells you how to decode it. For variant=evm it will be an ABI method definition
 // - The supplied value is passed through for each input parameter. It could be any JSON type (simple number/boolean/string, or complex object/array). The blockchain connection is responsible for serializing these according to the rules in the interface.
 type TransactionInput struct {
-	From     string           `json:"from"`
 	GasPrice *fftypes.JSONAny `json:"gasPrice,omitempty"` // can be a simple string/number, or a complex object - contract is between policy engine and blockchain connector
 	TransactionPrepareInputs
 }
 
 type TransactionPrepareInputs struct {
+	From   string            `json:"from"`
 	To     string            `json:"to"`
 	Nonce  *fftypes.FFBigInt `json:"nonce"`
 	Gas    *fftypes.FFBigInt `json:"gas,omitempty"`