Codex-style turn timeline and local conversation search for DeepSeek Harness Web

DeepSeek Harness 本地归档会话中心：全文搜索、回收站、撤销、自动保护快照与备份恢复。Local archived-chat search, recycle bin, undo, automatic protection snapshots, and backup restore for DeepSeek Harness.

Local and remote knowledge bases for DeepSeek Harness, with scoped recall, controlled write-back, and a Web management console