Save main window maximized state

Author: kalimag

src/BizHawk.Client.Common/config/Config.cs

@@ -142,6 +142,7 @@ public void SetWindowScaleFor(string sysID, int windowScale)
 		public bool StartFullscreen { get; set; }
 		public Point? MainWindowPosition { get; set; }
 		public Size? MainWindowSize { get; set; }
+		public bool MainWindowMaximized { get; set; }
 		public bool RunInBackground { get; set; } = true;
 		public bool AcceptBackgroundInput { get; set; }
 		public bool AcceptBackgroundInputControllerOnly { get; set; }

src/BizHawk.Client.EmuHawk/MainForm.cs

@@ -610,6 +610,11 @@ _argParser.SocketAddress is var (socketIP, socketPort)
 				{
 					Size = size;
 				}
+
+				if (Config.MainWindowMaximized)
+				{
+					WindowState = FormWindowState.Maximized;
+				}
 			}
 
 			if (Config.MainFormStayOnTop) TopMost = true;
@@ -2434,6 +2439,7 @@ private void SaveConfig(string path = "")
 					Config.MainWindowPosition = Location;
 					Config.MainWindowSize = Size;
 				}
+				Config.MainWindowMaximized = WindowState is FormWindowState.Maximized && !_inFullscreen;
 			}
 			else
 			{