```python
from fractions import Fraction

def combine_fractions(parts: list[str]) -> str:
    if not parts:
        raise ValueError("Input list cannot be empty")
    
    total = Fraction(0, 1)
    
    for part in parts:
        try:
            numerator, denominator = map(int, part.split('/'))
            fraction = Fraction(numerator, denominator)
            total += fraction
        except (ValueError, ZeroDivisionError):
            raise ValueError("Invalid fraction format or zero denominator")
    
    return str(total)
```