Module key 

P5-4 (§2 module 30): a terminal-library-agnostic key event — the crate::tui::state::TuiState::handle_key state machine consumes THIS type, not crossterm::event::KeyEvent, so the whole view-model core stays free of a crossterm/ratatui dependency (neither is in crates/harness’s Cargo.toml — see that crate’s own doc comment for why: a real terminal can’t be driven in a unit test, but this struct can be constructed by hand). crates/cli’s render/event-loop layer is the one place that translates a real crossterm::event::KeyEvent into this shape before handing it to the state machine.

Structs

KeyEvent

A Key plus the modifier keys held with it. Named fields (not a bitflag) so a test/keymap-string reader can construct one by hand without needing to know a bit layout.

Enums

Key

One logical key, independent of any terminal library’s own enum. #[non_exhaustive] so a future key (e.g. a specific F-key past F(12), or a media key) can be added without breaking a downstream match.