Lib.rs

src/
├── main.rs                     # Application entry point
├── error.rs                    # Centralized error handling
├── app/                        # Core application state and logic
│   ├── mod.rs                  # Module exports
│   ├── state.rs                # Core application state
│   ├── actions.rs              # State mutation functions
│   └── modals/                 # Modal-specific state and actions
│       ├── mod.rs              # Module exports
│       ├── search.rs           # Search modal state and actions
│       ├── purchase.rs         # Purchase modal state and actions
│       └── username.rs         # Username modal state and actions
├── api/                        # API client and request handling
│   ├── mod.rs                  # Module exports
│   ├── client.rs               # API client implementation
│   └── endpoints.rs            # API endpoint definitions
├── models/                     # Domain models
│   ├── mod.rs                  # Module exports
│   ├── member.rs               # Member/user models
│   ├── product.rs              # Product models
│   └── sale.rs                 # Sale/transaction models
├── ui/                         # User interface components
│   ├── mod.rs                  # Module exports
│   ├── events.rs               # Event handling
│   ├── layout.rs               # Layout definitions
│   ├── render.rs               # Main render function
│   └── components/             # UI components
│       ├── mod.rs              # Module exports
│       ├── header.rs           # Header components (title, username)
│       ├── products_list.rs    # Product list component
│       ├── user_panel.rs       # User info and sales panel
│       ├── modals/             # Modal components
│       │   ├── mod.rs          # Module exports
│       │   ├── search.rs       # Search modal
│       │   ├── purchase.rs     # Purchase modal
│       │   └── username.rs     # Username modal
│       └── helpers/            # Helper UI components
│           ├── mod.rs          # Module exports
│           ├── loading.rs      # Loading indicators
│           └── error.rs        # Error displays
├── config/                     # Configuration handling
│   ├── mod.rs                  # Module exports
│   ├── store.rs                # Config loading/saving
│   └── settings.rs             # Configuration definitions
└── utils/                      # Utility functions
    ├── mod.rs                  # Module exports
    ├── formatters.rs           # Formatting utilities
    └── helpers.rs              # General helper functions