implement the music game

src/main/java/emu/grasscutter/game/props/ActivityType.java

@@ -0,0 +1,38 @@
+package emu.grasscutter.game.props;
+
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.stream.Stream;
+
+@Getter
+@AllArgsConstructor
+public enum ActivityType {
+    NONE(0),
+    NEW_ACTIVITY_MUSIC_GAME(2202),
+
+    ;
+
+    private final int value;
+    private static final Int2ObjectMap<ActivityType> map = new Int2ObjectOpenHashMap<>();
+    private static final Map<String, ActivityType> stringMap = new HashMap<>();
+
+    static {
+        Stream.of(values()).forEach(e -> {
+            map.put(e.getValue(), e);
+            stringMap.put(e.name(), e);
+        });
+    }
+
+    public static ActivityType getTypeByValue(int value) {
+        return map.getOrDefault(value, NONE);
+    }
+
+    public static ActivityType getTypeByName(String name) {
+        return stringMap.getOrDefault(name, NONE);
+    }
+}