[Ui] - Give title to Gui and move greeting to the first action

Author: joel-lim

src/main/java/duke/Duke.java

@@ -23,13 +23,13 @@ public class Duke {
      * Runs the main loop of Duke.
      */
     public void run() {
+        ui.showGreeting();
+
         // Setup in-memory and disk storage
         String filePath = "data/tasks.txt";
         Storage storage = new TextStorage(filePath);
         TaskList tasks = loadTasks(storage);
 
-        ui.showGreeting();
-
         activate(new CommandHandler(tasks, ui, storage));
 
         saveTasks(tasks, storage);

src/main/java/duke/Main.java

@@ -35,6 +35,7 @@ public void start(Stage stage) {
         Gui gui = fxmlLoader.<Gui>getController();
         gui.setDuke(duke);
 
+        stage.setTitle("Duke");
         stage.setScene(scene);
         stage.resizableProperty().setValue(false);
         // Handle case where user manually exits