90% of the app is already running on Replit with AI-driven product recommendations; now I need the commerce and install-ready pieces finished. Shopping cart & Stripe I have Stripe set up in test mode and a basic product catalogue ready. Your task is to wire in a streamlined checkout flow. It must support: • guest checkout • an order summary page with shipping info shown before payment • a clear confirmation screen after payment succeeds Authentication Users should be able to sign in with either Google or a classic email/password flow. Please implement secure JWT sessions so the same account can be used across web and the future mobile wrapper. Progressive Web App Once checkout and login are solid, convert the entire site into a PWA: add the manifest, service worker with offline fallback, and the “install” prompt so users can save it to their home screen. Lighthouse scores for PWA should pass without manual tweaks on my side. Stack notes Everything runs on Replit, so stick to the built-in deployment environment. I’m comfortable with Express, React and plain JavaScript—feel free to choose whichever keeps the codebase clean, but keep dependencies lightweight. Acceptance I’ll consider the work complete when: 1. A visitor can browse items, check out with Stripe, and see the confirmation screen. 2. The same visitor can create an account via Google or email/password and see past orders tied to that account. 3. The site installs as a PWA and loads offline for cached pages. 4. All code and environment variables are committed back to the Replit repo with clear README setup steps. If that outline matches your skill set, I’ll share the repo link so you can start right away.