Lots of SzGui work

SzGui/Windows/SzGuiWindowBase.cs

@@ -0,0 +1,22 @@
+using ImGuiNET;
+
+namespace SzGui.Windows;
+
+public abstract class SzGuiWindowBase
+{
+    public bool IsOpen = true;
+    public string WindowName { get; protected set; } = "Window";
+    
+    public virtual void Draw()
+    {
+        if (!IsOpen) return;
+        
+        if (ImGui.Begin(WindowName, ref IsOpen, ImGuiWindowFlags.MenuBar))
+        {
+            RenderContent();
+        }
+        ImGui.End();
+    }
+
+    protected abstract void RenderContent();
+}