harshj111186/stock-app-v2 ? reverse-engineered prompt

Build me a stock manager web app for a shop that feels clean and easy to use, with a dashboard, login, items page, godown pages, and a transactions page. I want it to be a modern Next.js app with a nice mobile friendly layout, simple sidebar navigation, top bar, and reusable UI components, using Tailwind and icon based controls. It should connect to Supabase for auth and data, and be set up so it can be deployed as a static site on GitHub Pages.

Please make the main flow feel solid first, especially the UI foundation and data quality, so I can later expand into inventory actions, more transaction types, and reports. Add sensible empty states, loading states, and basic validation so it does not feel rough. If anything in the current setup is unclear, look up the latest docs online and keep it compatible with the current stack.