Constant input::KEYEVENT_HELP

pub(crate) const KEYEVENT_HELP: &str = r#"Injects a single key event.

This command simulates a single key down + up sequence. The argument is a decimal HID usage
`code`, prior to any remapping the IME may do.

Common usage codes:

key       | code
----------|-----
enter     | 40
escape    | 41
backspace | 42
tab       | 43

The time between the down and up report is `--duration`."#;