Integrate Outlit SDK for customer journey tracking and analytics. Triggers when users need to add Outlit to React, Next.js, Vue, Svelte, Angular, Astro, Node.js, Express, or Fastify apps. Covers SDK installation (@outlit/browser, @outlit/node), auth provider integration (Clerk, NextAuth, Supabase, Auth0, Firebase), GDPR consent management, event tracking, user lifecycle events (activate, engaged, inactive), customer billing status (trialing, paid, churned), and Stripe webhook integration.