refactor(demos): update machining demos and remove legacy demo message handling

Made-with: Cursor

Machining/DemoBuildGeomOnlyMachiningProject.cs

@@ -42,7 +42,8 @@ public static class DemoBuildGeomOnlyMachiningProject
 
 	static void Main()
 	{
-		LocalApp.AppBegin();
+		using var loggerFactory = Microsoft.Extensions.Logging.LoggerFactory.Create(b => b.AddConsole());
+		LocalApp.AppBegin(loggerFactory.CreateLogger("Hi.Sample"));
 		LocalProjectService localProjectService = new LocalProjectService();
 
 		var projectPath = "C:/HiNC-Projects/NewProject/Main.hincproj";

Machining/DemoBuildMachiningProject.cs

@@ -142,7 +142,8 @@ public static class DemoBuildMachiningProject
 	[STAThread]
 	static void Main()
 	{
-		LocalApp.AppBegin();
+		using var loggerFactory = Microsoft.Extensions.Logging.LoggerFactory.Create(b => b.AddConsole());
+		LocalApp.AppBegin(loggerFactory.CreateLogger("Hi.Sample"));
 		LocalProjectService localProjectService = new LocalProjectService();
 
 		var projectPath = "C:/HiNC-Projects/NewProject/Main.hincproj";

Machining/DemoUseMachiningProject.cs

@@ -21,7 +21,8 @@ public static class DemoUseMachiningProject
 {
 	static void Main()
 	{
-		LocalApp.AppBegin();
+		using var loggerFactory = Microsoft.Extensions.Logging.LoggerFactory.Create(b => b.AddConsole());
+		LocalApp.AppBegin(loggerFactory.CreateLogger("Hi.Sample"));
 		LocalProjectService localProjectService = new LocalProjectService();
 
 		#region ProjectLoading