dsh-approval-comment: Add "Reject with comment" to DSH Web Approval

# Introduction If you are running agents using DSH (DeepSeek Harness) in web mode, you have likely encountered these two issues: 1. When a tool call triggers an approval window and you click "Reject," the model does not stop; instead, it proceeds to the next round of reasoning, guessing the reason for your rejection and continuing with an alternative plan. 2. When you manually stop a task, the rejection is not added to the model's context, and subsequent requests proceed as if nothing happened. In real-world collaboration, refusals typically come with a reason: "Do not touch this file; move it to the working directory." The default approval process neither captures this reason nor allows the model to rethink based on it. `dsh-approval-comment` is a plugin designed to fill this gap. # What is this? `dsh-approval-comment` is a...