Expense Tracker Flutter App UI

Build a complete expense tracker app UI in Flutter with Google Antigravity, starting from the default Flutter project. Includes a balance dashboard, searchable transactions, add/edit/delete with undo, category donut and monthly bar charts, budget progress, and light/dark themes. Customize the app name, currency, accent color, and style with simple variables. Local demo data only: no backend, no API keys, no extra packages.