snapshot

Task-state snapshots for session handoff. Write a resumable snapshot when wrapping up, restore from it when picking the work back up, trusting its decisions and re-checking its facts. Use when the user says 打个快照 / 交接 / 收尾下次接着做 / 换个会话继续 / 上次做到哪了 / 快没上下文了先记下进度 / snapshot this task / handoff / wrap up this session / pick up where we left off. Do not trigger for jest/vitest test snapshots, VM/database/filesystem…