added splashscreen, login and add hp number pages

lib/app/core/custom_base_view_model.dart

@@ -0,0 +1,16 @@
+import 'package:stacked/stacked.dart';
+import 'package:stacked_services/stacked_services.dart';
+
+import '../app.locator.dart';
+
+class CustomBaseViewModel extends BaseViewModel {
+  final dialogService = locator<DialogService>();
+  final navigationService = locator<NavigationService>();
+  final bottomSheetService = locator<BottomSheetService>();
+  final snackbarService = locator<SnackbarService>();
+  bool backPressed = true;
+
+  void back() {
+    navigationService.back();
+  }
+}