Add packet type (unused yet)

src/main/java/io/akarin/server/core/PacketType.java

@@ -0,0 +1,5 @@
+package io.akarin.server.core;
+
+public enum PacketType { // unused yet
+    UNKNOWN;
+}

src/main/java/net/minecraft/server/Packet.java

@@ -20,4 +20,10 @@ public interface Packet<T extends PacketListener> {
     default boolean a() {
         return false;
     }
+
+    // Akarin start
+    public default io.akarin.server.core.PacketType getType() {
+        return io.akarin.server.core.PacketType.UNKNOWN;
+    }
+    // Akarin end
 }