Write a function shuffle that accepts an array and returns a new array with the elements in randomized order. Ensure that all elements from the original array are present exactly once and that the original array is not mutated.
Example Inputs & Outputs
Input: [1, 2, 3, 4, 5]
Possible Output: [3, 1, 5, 2, 4]
Input: ['a', 'b', 'c']
Possible Output: ['b', 'c', 'a']
Constraints & Edge Cases
- The function should return a new array (do not mutate the original).
- All original elements must be present exactly once.
- An empty array should return an empty array.
- Input array may contain duplicates (handle gracefully).
- The output should be randomized on each function call.
