"""Format a date/datetime to be more human-readable.

Converts datetime objects or ISO strings to a format like "Jan 15, 2024 at 2:30 PM". 
If the input is None or empty, returns "—". For string inputs, attempts to parse common ISO formats. 
If parsing fails, truncates the string to a maximum of 16 characters. For datetime objects, 
formats them directly. For other types, converts to string and truncates to 16 characters.

Args:
    date_value: A datetime object, ISO format string, or other type representing a date/time.

Returns:
    str: A human-readable date string or a truncated representation of the input.
"""
You should write code starting with:
from datetime import datetime

def human_date(date_value) -> str:
    # TODO: Implement this function
    pass

