/**
 * Classifies a human's turn input during plan negotiation. The human's text is
 * free-form, but we detect explicit approval/reopen tokens to drive the state
 * machine — never infer approval from vague positivity (anti-sycophancy applies
 * to the human side too: only an explicit token freezes).
 *
 * Returns:
 *   "approve"   — the input is exactly "approve" (case-insensitive, optionally
 *                 prefixed with `/`): freeze the plan.
 *   "reopen"    — the input is exactly "reopen" (case-insensitive, optionally
 *                 prefixed with `/`): reopen a frozen plan.
 *   "challenge" — anything else, including phrases that CONTAIN "approve" or
 *                 "reopen" but aren't the bare token. Treated as a challenge
 *                 to the plan, prompting a negotiation turn.
 *
 * Pure (no I/O) so it is unit-tested directly.
 */
export type TurnIntent = "approve" | "reopen" | "challenge";
export declare function classifyTurn(input: string): TurnIntent;