e2e: use ed25519 for secretConn (remote signer) (#5678)

## Description

Hardcode ed25519 to dialTCPFn in e2e tests. 

I will backport `DefaultRequestHandler` fixes

This will be replaced when grpc is implemented.

privval/signer_requestHandler.go

@@ -24,14 +24,17 @@ func DefaultValidationRequestHandler(
 	switch r := req.Sum.(type) {
 	case *privvalproto.Message_PubKeyRequest:
 		if r.PubKeyRequest.GetChainId() != chainID {
-			res = mustWrapMsg(&privvalproto.SignedVoteResponse{
-				Vote: tmproto.Vote{}, Error: &privvalproto.RemoteSignerError{
+			res = mustWrapMsg(&privvalproto.PubKeyResponse{
+				PubKey: cryptoproto.PublicKey{}, Error: &privvalproto.RemoteSignerError{
 					Code: 0, Description: "unable to provide pubkey"}})
 			return res, fmt.Errorf("want chainID: %s, got chainID: %s", r.PubKeyRequest.GetChainId(), chainID)
 		}
 
 		var pubKey crypto.PubKey
 		pubKey, err = privVal.GetPubKey()
+		if err != nil {
+			return res, err
+		}
 		pk, err := cryptoenc.PubKeyToProto(pubKey)
 		if err != nil {
 			return res, err
@@ -64,8 +67,8 @@ func DefaultValidationRequestHandler(
 
 	case *privvalproto.Message_SignProposalRequest:
 		if r.SignProposalRequest.GetChainId() != chainID {
-			res = mustWrapMsg(&privvalproto.SignedVoteResponse{
-				Vote: tmproto.Vote{}, Error: &privvalproto.RemoteSignerError{
+			res = mustWrapMsg(&privvalproto.SignedProposalResponse{
+				Proposal: tmproto.Proposal{}, Error: &privvalproto.RemoteSignerError{
 					Code:        0,
 					Description: "unable to sign proposal"}})
 			return res, fmt.Errorf("want chainID: %s, got chainID: %s", r.SignProposalRequest.GetChainId(), chainID)

test/e2e/app/main.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/tendermint/tendermint/abci/server"
 	"github.com/tendermint/tendermint/config"
+	"github.com/tendermint/tendermint/crypto/ed25519"
 	tmflags "github.com/tendermint/tendermint/libs/cli/flags"
 	"github.com/tendermint/tendermint/libs/log"
 	tmnet "github.com/tendermint/tendermint/libs/net"
@@ -178,7 +179,7 @@ func startSigner(cfg *Config) error {
 	var dialFn privval.SocketDialer
 	switch protocol {
 	case "tcp":
-		dialFn = privval.DialTCPFn(address, 3*time.Second, filePV.Key.PrivKey)
+		dialFn = privval.DialTCPFn(address, 3*time.Second, ed25519.GenPrivKey())
 	case "unix":
 		dialFn = privval.DialUnixFn(address)
 	default: