Alleging she was hit by a car when she was forced to step onto Touhy Avenue because an unnatural accumulation of snow and ice from careless plowing made a sidewalk in Park Ridge impassable, Lorraine Pattullo-Banks sued the city for negligence. But the city — arguing Pattullo-Banks wasn’t an intended user of that portion of the street because she wasn’t walking an area marked as a crosswalk &mdash …