Pickups + Save-diff

scripts/core/SaveManager.cs

@@ -0,0 +1,36 @@
+using Godot;
+using System.Text.Json;
+
+public partial class SaveManager : Node
+{
+	public SaveState State { get; private set; } = new();
+
+	private const string SavePath = "user://save.json";
+
+	public override void _Ready()
+	{
+		Load();
+	}
+
+	public void Load()
+	{
+		if (!FileAccess.FileExists(SavePath))
+		{
+			GD.Print("No save found, starting fresh.");
+			State = new SaveState();
+			return;
+		}
+
+		var json = FileAccess.GetFileAsString(SavePath);
+		State = JsonSerializer.Deserialize<SaveState>(json) ?? new SaveState();
+		GD.Print($"Loaded save. CollectedPickups={State.CollectedPickups.Count}");
+	}
+
+	public void Save()
+	{
+		var json = JsonSerializer.Serialize(State, new JsonSerializerOptions { WriteIndented = true });
+		using var f = FileAccess.Open(SavePath, FileAccess.ModeFlags.Write);
+		f.StoreString(json);
+		GD.Print("Saved.");
+	}
+}