signer/core: move API JSON types to separate package (#23275)

This PR moves (some) account types into a standalone package, to avoid
depending on signer/core from accounts/external.

cmd/clef/main.go

@@ -50,10 +50,10 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/ethereum/go-ethereum/signer/core"
+	"github.com/ethereum/go-ethereum/signer/core/apitypes"
 	"github.com/ethereum/go-ethereum/signer/fourbyte"
 	"github.com/ethereum/go-ethereum/signer/rules"
 	"github.com/ethereum/go-ethereum/signer/storage"
-
 	"github.com/mattn/go-colorable"
 	"github.com/mattn/go-isatty"
 	"gopkg.in/urfave/cli.v1"
@@ -923,7 +923,7 @@ func testExternalUI(api *core.SignerAPI) {
 		time.Sleep(delay)
 		data := hexutil.Bytes([]byte{})
 		to := common.NewMixedcaseAddress(a)
-		tx := core.SendTxArgs{
+		tx := apitypes.SendTxArgs{
 			Data:     &data,
 			Nonce:    0x1,
 			Value:    hexutil.Big(*big.NewInt(6)),
@@ -1055,11 +1055,11 @@ func GenDoc(ctx *cli.Context) {
 		data := hexutil.Bytes([]byte{0x01, 0x02, 0x03, 0x04})
 		add("SignTxRequest", desc, &core.SignTxRequest{
 			Meta: meta,
-			Callinfo: []core.ValidationInfo{
+			Callinfo: []apitypes.ValidationInfo{
 				{Typ: "Warning", Message: "Something looks odd, show this message as a warning"},
 				{Typ: "Info", Message: "User should see this as well"},
 			},
-			Transaction: core.SendTxArgs{
+			Transaction: apitypes.SendTxArgs{
 				Data:     &data,
 				Nonce:    0x1,
 				Value:    hexutil.Big(*big.NewInt(6)),
@@ -1075,7 +1075,7 @@ func GenDoc(ctx *cli.Context) {
 		add("SignTxResponse - approve", "Response to request to sign a transaction. This response needs to contain the `transaction`"+
 			", because the UI is free to make modifications to the transaction.",
 			&core.SignTxResponse{Approved: true,
-				Transaction: core.SendTxArgs{
+				Transaction: apitypes.SendTxArgs{
 					Data:     &data,
 					Nonce:    0x4,
 					Value:    hexutil.Big(*big.NewInt(6)),