// reservedClassifyKeys are single-character keys the classify TUI handles
// itself (see tui/classify.go). User bindings to these keys would be silently
// overridden by the TUI, so we reject them at config-load time.
var reservedClassifyKeys = map[string]string{
	",": "previous segment",
	".": "next segment",
	"0": "confirm label at certainty 100",
	" ": "open comment dialog",
}

			os.Exit(1)
		}
		if purpose, reserved := reservedClassifyKeys[key]; reserved {
			fmt.Fprintf(os.Stderr,
				"Error: binding key %q in %s is reserved by the TUI for %s — pick a different key.\n",
				key, cfgPath, purpose)

Config-load rejects bindings that collide with keys the TUI reserves for its own
commands (`,` previous segment, `.` next segment, `0` confirm at certainty 100,
space opens the comment dialog). Previously these were silently shadowed by the
TUI hotkey and the user's binding did nothing.