Last Digit of Factorial

### Problem Statement  
Write a Python function `last_digit_factorial(n)` that computes the last digit of the factorial of a given non-negative integer `n`.  

The factorial of a number `n` is the product of all positive integers less than or equal to `n`. For example:  
- `5! = 5 × 4 × 3 × 2 × 1 = 120`  

The last digit of `5!` is `0`.  

#### Function Signature  
```python [main.nopy]
def last_digit_factorial(n: int) -> int:
    pass
```

#### Input  
- `n` (int): A non-negative integer.  

#### Output  
- (int): The last digit of the factorial of `n`.  

#### Examples  
```python [main.nopy]
last_digit_factorial(4)  # Output: 4
last_digit_factorial(5)  # Output: 0
last_digit_factorial(10) # Output: 0
```

#### Constraints  
- The input `n` will be a non-negative integer.  
- The function should handle large values of `n` efficiently.