Application state and event handling - How the App struct in src/app.rs holds UI state, routes AppEvent values (keys, WhatsApp, AI, timers, web panel), handles function keys, the list filter and chat deletion, toggles global and per-chat autoreply, and runs background tasks.
Runtime and event loop - Process startup in src/main.rs, the tokio runtime, the two event channels, the input thread, the WhatsApp forwarder, the optional web panel thread and the draw/recv TUI loop.
Terminal UI rendering - How src/ui.rs draws the connecting, QR pairing and main screens with ratatui, including the filtered list with global autoreply marker, message formatting, wrapping, the input box and the footer key help.
