feat:register page ui done

lib/core/helpers/validator_helpers.dart

@@ -0,0 +1,28 @@
+import 'package:food_delivery_client/core/core.dart';
+
+abstract class Validators {
+  static String? validatePhoneNumber(String phoneNumber) {
+    if (phoneNumber.isEmpty) {
+      return navigatorKey.currentContext?.loc.field_cannot_be_empty;
+    } else if (phoneNumber.length < 12) {
+      return navigatorKey.currentContext?.loc.invalid_phone_format;
+    }
+    return null;
+  }
+
+  static String? validatePassword(String password) {
+    if (password.isEmpty) {
+      return navigatorKey.currentContext?.loc.field_cannot_be_empty;
+    } else if (password.length < 6) {
+      return navigatorKey.currentContext?.loc.password_too_short;
+    }
+    return null;
+  }
+
+  static String? validateFields(String value) {
+    if (value.isEmpty) {
+      return navigatorKey.currentContext?.loc.field_cannot_be_empty;
+    }
+    return null;
+  }
+}