```python
"""Close out a stockroom count sheet after a day's receive and issue moves."""
import re


def closing_sheet(opening: str, moves: str) -> str:
    if not isinstance(opening, str) or not isinstance(moves, str):
        raise ValueError("closing_sheet expects two strings")

    def parse_sheet(text):
        held = {}
        if text == "":
            return held
        for part in text.split(";"):
            name, colon, count = part.partition(":")
            if colon == "":
                raise ValueError(f"sheet entry has no colon: {part}")
            if re.fullmatch(r"[a-z]+", name) is None:
                raise ValueError(f"bad item name: {part}")
            if re.fullmatch(r"0|[1-9]\d*", count) is None:
                raise ValueError(f"bad count: {part}")
            if name in held:
                raise ValueError(f"duplicate sheet entry: {name}")
            held[name] = int(count)
        return held

    def apply_move(sheet, move):
        parts = move.split("+")
        action = parts[0]
        quantity = int(parts[1])
        item = action[:-quantity]

        if action.startswith("issue"):
            if item not in sheet:
                raise ValueError(f"cannot issue {item}: no such item on hand")
            if quantity > sheet[item]:
                raise ValueError(f"cannot issue {quantity} of {item}: only {sheet[item]} left")
            sheet[item] -= quantity
        elif action.startswith("receive"):
            sheet[item] += quantity
        else:
            raise ValueError(f"invalid move: {move}")

    held = parse_sheet(opening)
    
    if moves == "":
        return ";".join(entry for entry in sorted(held) if held[entry] > 0)

    for move in moves.split(";"):
        apply_move(held, move)

    entries = []
    for name in sorted(held):
        if held[name] > 0:
            entries.append(f"{name}:{held[name]}")
    return ";".join(entries)
```