[#932] adm: Rename util to helper

To avoid conflicts with `util` packages in other imports.

Signed-off-by: Anton Nikiforov <an.nikiforov@yadro.com>

cmd/frostfs-adm/internal/modules/morph/helper/group.go

@@ -0,0 +1,39 @@
+package helper
+
+import (
+	"encoding/json"
+
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
+	"github.com/nspcc-dev/neo-go/pkg/util"
+	"github.com/nspcc-dev/neo-go/pkg/wallet"
+)
+
+func AddManifestGroup(cw *wallet.Wallet, h util.Uint160, cs *ContractState) error {
+	priv := cw.Accounts[0].PrivateKey()
+	pub := priv.PublicKey()
+
+	sig := priv.Sign(h.BytesBE())
+	found := false
+
+	for i := range cs.Manifest.Groups {
+		if cs.Manifest.Groups[i].PublicKey.Equal(pub) {
+			cs.Manifest.Groups[i].Signature = sig
+			found = true
+			break
+		}
+	}
+	if !found {
+		cs.Manifest.Groups = append(cs.Manifest.Groups, manifest.Group{
+			PublicKey: pub,
+			Signature: sig,
+		})
+	}
+
+	data, err := json.Marshal(cs.Manifest)
+	if err != nil {
+		return err
+	}
+
+	cs.RawManifest = data
+	return nil
+}