dsh-temp-chat: Temporary Chat Assistant for DSH Page

The `dsh-temp-chat` plugin for DeepSeek Harness (DSH) is designed to meet the need for temporary conversations during development and debugging that do not require persistent records. It is a lightweight floating component with a whale icon entry, supporting Chinese/English switching, dragging, minimizing, and streaming output. By default, it reuses the DSH session configuration and also supports custom OpenAI-compatible endpoints. All data is stored only in browser memory, avoiding session-history pollution and privacy leaks, making it well suited for developers to quickly test prompts. Installation requires DSH to support a web or desktop profile.