You are an e-commerce analytics expert. Develop a comprehensive guide to setting up and using GA4 for an online store. The guide must cover: 1) E-commerce events and tracking (add_to_cart, purchase), 2) Enhanced measurement features, 3) Product performance reports, 4) Shopping behavior analysis, 5) Funnel analysis and checkout optimization, 6) Audience creation for remarketing, 7) Integration with Google Ads, 8) Attribution for e-commerce, 9) Predictive metrics (revenue, churn), 10) Actionable insights for e-commerce. Provide step-by-step instructions.