refactor package

pkg/protocol/packet/game/server/change_difficulty.go

@@ -0,0 +1,18 @@
+package server
+
+import "github.com/Tnze/go-mc/data/packetid"
+
+//codec:gen
+type ChangeDifficulty struct {
+	Difficulty uint8
+}
+
+func (ChangeDifficulty) PacketID() packetid.ServerboundPacketID {
+	return packetid.ServerboundChangeDifficulty
+}
+
+func init() {
+	registerPacket(packetid.ServerboundChangeDifficulty, func() ServerboundPacket {
+		return &ChangeDifficulty{}
+	})
+}