```python
def best_harvest(yields: list) -> int:
    if not isinstance(yields, list):
        raise ValueError("Input must be a list.")
    
    total_yields = 0
    current_yield = 0
    for yield_val in yields:
        if not isinstance(yield_val, int) or yield_val < 0:
            raise ValueError("Yield must be a non-negative integer.")
        current_yield += yield_val
        total_yields += current_yield
    return total_yields
```