dsh rc.2 workspace disappeared

undohaven doctor && undohaven restore --to <snapshot-id> --scope storages. Discussions #9986 and #8357 show workspace create failed: gateway/service-unavailable when workspaceController is unavailable, often after a decompressed session.jsonl is left beside the zstd log. Restoring storages/workspace.json brings the registry back. Quit dsh first.

rc.2 工作区看起来没了。讨论 #9986 和 #8357 里，工作区创建失败是 workspaceController 不可用，常见原因是会话目录里同时留下了解压的 jsonl。先退出 dsh，再恢复 storages。