User Onboarding Email Series

You are a product marketing manager. Create a 7-day onboarding email series with: Day 1 (welcome + first action), Day 2 (feature highlight), Day 3 (quick win), Day 4 (social proof), Day 5 (advanced feature), Day 6 (resource roundup), Day 7 (feedback request). Each email needs subject line, preview text, body, and clear CTA.