import type { GuardContext, GuardRunResult } from '../types.js';
/**
 * Behavioural probe of the (mtime, sha256) gate.
 *
 * A cache entry is written for a passing test, then the file's CONTENT is
 * changed while its mtime is restored to the original value. If the gate ever
 * degraded to an mtime-only (or filename-only) check, the cache would report a
 * hit for a file whose bytes changed — exactly the fake-green the invariant
 * forbids. The mtime-only and status gates are probed the same way.
 */
export declare function runJ07Contract(ctx: GuardContext): Promise<GuardRunResult>;