-----Description-----  
This task requires writing a Lean 4 method that rotates a list of integers to the right by a specified number of positions. The method should produce a new list where each element is shifted to the right while preserving the original list's length.

-----Input-----  
The input consists of:  
• l: A list of integers.  
• n: A non-negative natural number that indicates the number of positions by which to rotate the list.

-----Output-----  
The output is a list of integers:  
• Returns a list with the same length as the input list, where the elements have been rotated to the right by n positions.

-----Note-----  
• The precondition requires that n is non-negative.  
• If the input list is empty, it should be returned unchanged.