-----Description----- 
This task requires writing a Lean 4 method that rearranges an array of integers by moving all zero values to the end of the array. The method should ensure that the relative order of the non-zero elements remains the same, the overall size of the array is unchanged, and the number of zeroes in the array stays constant.

-----Input-----
The input consists of:
arr: An array of integers.

-----Output-----
The output is an array of integers:
Returns an array where:
- The length is the same as that of the input array.
- All zero values are positioned at the end.
- The relative order of non-zero elements is preserved.
- The count of zero values remains the same as in the input array.

-----Note-----
There are no preconditions; the method will always work for any array of integers.