Rattles Terminal Spinners

You're building a CLI app in Rust and need a loading spinner. Rattles gives you that with zero dependencies and a clever stateless design,just call `current_frame()` in your render loop, no lifecycle management needed. It ships with preset collections (braille dots, arrows, emoji) and works in `no_std` environments if you switch to tick-based or index-based driving. The `rattle!` macro lets you define custom spinners at compile time. It integrates cleanly with ratatui since you can pass the spinner by reference anywhere without wrapping it in `Arc<Mutex>`. The stateless-by-default approach is refreshing for something this simple, and the fallback options make it work even on embedded targets.