Anooppandikashala/invoiso ? reverse-engineered prompt

Build me a free offline invoice and billing app for desktop that works on Windows, Linux, and macOS.

I want it to let me create professional PDF invoices and quotations, manage customers and products, track payments, and keep everything stored locally on my computer with no cloud account or internet needed. It should have a clean dashboard, support multiple currencies, GST details, and a UPI QR code on invoices. I also want different invoice styles like classic, modern, and minimal, plus the ability to clone invoices, export CSV files, and move deleted items to a trash area I can restore from.

Please include simple login with admin and normal user access, password change on first sign in, and admin only settings for company info, backups, and restoring data. Add reports for revenue, tax, top customers, top products, and payment status. If you need current docs or any small implementation details, look them up online as you go.