Add Approval and Completion Notifications to DeepSeek Harness Webpage with dsh-web-ui-notify

`dsh-web-ui-notify` is a DeepSeek Harness Web UI notification plugin maintained by bill9109. When the tab is left, system notifications will pop up for tool approval, DSH questions and round completion, with the session name in the title, and clicking the notification will jump back to the corresponding session. This article verifies the 0.1.3 installation, web profile, setting switches and permission boundaries according to the community directory and repository README.