dsh-zhihu-dashboard: Add a Zhihu dashboard and seven agent tools to DeepSeek Harness.

# Introduction For agent development, Zhihu is often an indispensable information source: choosing topics requires checking the hot list, following answers to specific questions, and monitoring updates from certain authors. The existing approach involves switching to the browser, reading the content, and then pasting the link and summary back into the agent conversation, causing a break in information flow between two copy-paste actions. DSH's philosophy is "Everything is a plugin." The `dsh-zhihu-dashboard` introduced below brings this capability into DeepSeek Harness (DSH): it opens a Zhihu panel in the UI sidebar to handle viewing and tracking, while simultaneously registering seven native tools within the conversation to allow the agent to directly check the hot list and search for content. # What is it `dsh-zhihu-dashboard` is a DSH plugin maintained by kexuejin under the MIT license.