Monarch Books is getting a mural on this side of the business, but it wasnt an easy decision for city leaders."What's your story?" It's a simple question and it sparked a recent debate at Arroyo Grande City Hall. The question is the centerpiece of a proposed mural in the Village, but not everyone agrees it belongs there.Taneesha Regez owns Monarch Books on East Branch Street. She said the design will include birds, ships, and a UFO with a tracto…