Remove FakeComponentFactory dependency on Examples namespace

- Removed Terminal.Gui.Examples using statement from FakeComponentFactory
- Removed key injection logic from FakeComponentFactory.CreateInput()
- Created ExampleContextInjector to handle key injection via Application.Driver.EnqueueKeyEvent
- Updated examples to call ExampleContextInjector.SetupAutomaticInjection() before Init
- This addresses @tig's comment to use Driver.EnqueueKeyEvent instead of direct FakeInput injection

Co-authored-by: tig <585482+tig@users.noreply.github.com>

Examples/Example/Example.cs

@@ -20,6 +20,9 @@ using Terminal.Gui.Views;
 ConfigurationManager.RuntimeConfig = """{ "Theme": "Light" }""";
 ConfigurationManager.Enable (ConfigLocations.All);
 
+// Setup automatic key injection for testing
+ExampleContextInjector.SetupAutomaticInjection ();
+
 // Check for test context to determine driver
 string? contextJson = Environment.GetEnvironmentVariable (ExampleContext.ENVIRONMENT_VARIABLE_NAME);
 string? driverName = null;