add needed rules for the provided name (first nd last)

lib/features/menu/bloc/profile_bloc/profile_bloc.dart

@@ -262,6 +262,17 @@ class ProfileBloc extends Bloc<ProfileEvent, ProfileState> {
     if (parts.any((part) => part.length < 2 || part.length > 30)) {
       return 'Full name parts must be between 2 and 30 characters long';
     }
+    if (RegExp(r"\s{2,}").hasMatch(value)) {
+      return 'Only one space is allowed between first and last names';
+    }
+    // Check for leading or trailing spaces
+    if (value != value.trim()) {
+      return 'No leading or trailing spaces allowed';
+    }
+    // Check if only alphabetic characters and one space are used
+    if (!RegExp(r'^[A-Za-z]+(?: [A-Za-z]+)?$').hasMatch(value)) {
+      return 'Only alphabetic characters and a single space are allowed';
+    }
     return null;
   }