Fix FXML errors and make Analytics accessible to all users

src/main/java/org/example/petshopdesktop/controllers/AnalyticsController.java

@@ -55,13 +55,6 @@ public class AnalyticsController {
 
     @FXML
     public void initialize() {
-        if (!UserSession.getInstance().isAdmin()) {
-            lblError.setText("Access restricted to administrators only.");
-            lblError.setVisible(true);
-            disableAllCharts();
-            return;
-        }
-
         configureCharts();
         loadAnalyticsData();
     }

src/main/java/org/example/petshopdesktop/controllers/MainLayoutController.java

@@ -174,8 +174,8 @@ public class MainLayoutController {
     public void initialize() {
         applyRBAC();
 
-        loadView("pet-view.fxml");
-        updateButtons(btnPets);
+        loadView("analytics-view.fxml");
+        updateButtons(btnAnalytics);
     }
 
     private void applyRBAC() {
@@ -204,11 +204,6 @@ public class MainLayoutController {
             btnStaffAccounts.setManaged(isAdmin);
         }
 
-        if (btnAnalytics != null) {
-            btnAnalytics.setVisible(isAdmin);
-            btnAnalytics.setManaged(isAdmin);
-        }
-
         btnSalesHistory.setText(isAdmin ? "Sales History" : "Sales");