Add MeleeEffect and related services for combat interactions

GameCore/State/GameStateService.cs

@@ -0,0 +1,40 @@
+using GameCore.ECS;
+using GameCore.Events;
+
+namespace GameCore.State;
+
+public class GameStateService(World world) : IGameStateService
+{
+    private readonly HashSet<string> _unlockedLevelIds = [];
+    private readonly World _world = world;
+    public GameStatus CurrentStatus { get; private set; } = GameStatus.InMainMenu;
+    public string CurrentLevelId { get; private set; }
+    public IReadOnlyCollection<string> UnlockedLevelIds => _unlockedLevelIds;
+
+    public void SetStatus(GameStatus newStatus)
+    {
+        if (CurrentStatus == newStatus) return;
+
+        CurrentStatus = newStatus;
+        _world.PublishEvent(new GameStatusChangedEvent(newStatus));
+    }
+
+    public void StartGame(string startingLevelId)
+    {
+        CurrentLevelId = startingLevelId;
+        _unlockedLevelIds.Add(startingLevelId);
+        SetStatus(GameStatus.InGame);
+    }
+
+    public void UnlockLevel(string levelId)
+    {
+        _unlockedLevelIds.Add(levelId);
+    }
+
+    public void ResetProgress()
+    {
+        _unlockedLevelIds.Clear();
+        CurrentLevelId = null!;
+        SetStatus(GameStatus.InMainMenu);
+    }
+}

GameCore/State/GameStatus.cs

@@ -0,0 +1,9 @@
+namespace GameCore.State;
+
+public enum GameStatus
+{
+    InMainMenu,
+    InGame,
+    Paused,
+    GameOver
+}

GameCore/State/IGameStateService.cs

@@ -0,0 +1,13 @@
+namespace GameCore.State;
+
+public interface IGameStateService
+{
+    GameStatus CurrentStatus { get; }
+    string CurrentLevelId { get; }
+    IReadOnlyCollection<string> UnlockedLevelIds { get; }
+
+    void SetStatus(GameStatus newStatus);
+    void StartGame(string startingLevelId);
+    void UnlockLevel(string levelId);
+    void ResetProgress();
+}