dsh-notification-sounds: Add "Task Waiting" and "Task Completed" sounds to DSH Web UI

**Introduction** When using DeepSeek Harness (DSH) to run tasks, the typical workflow is to delegate the work to an agent and switch to handling other matters. The problem is that you don't know when to return: the task might be waiting for your approval, or it may have finished long ago. Consequently, you have to repeatedly switch back to the page to check progress, your attention gets fragmented, and you might not find any new progress upon returning. **dsh-notification-sounds** solves this issue with two sounds: it plays "Task Waiting" when the AI requires your intervention, and "Task Completed" when the main session and all sub-agents finish stably. You simply return when you hear the sound. Below, I introduce the positioning, features, and complete installation steps of this plugin. **What is this?** **dsh-notification-sounds** is a browser extension for **DeepSeek Harness**.