dsh-totp: TOTP Access Verification for DeepSeek Harness Web Instances

DeepSeek Harness (DSH) introduces the dsh-totp plugin, providing TOTP-based one-time password access control for local web instances. The plugin supports Google/Microsoft Authenticator and offers QR code binding, one-click lock, recovery codes, and account locking, without requiring additional services or relying on third-party account login. It is compatible with various request methods such as Fetch, XHR, and WebSocket, and supports both LAN and remote access. The installation command is `dsh plugin --profile web add dsh-totp`, and it takes effect once launched.