dsh-toc-tail: Session Timeline and One-Click Backtrack for DeepSeek Harness Web Interface

# Introduction After scrolling through a long conversation in the web interface, two issues become apparent: locating a specific request relies solely on scrolling; and when attempting to revert to a previous request, handling the content that follows a recalled message is not intuitive. `dsh-toc-tail` addresses exactly these two problems. It compresses each user request into a horizontal line on a vertical timeline located to the right of the session column. The TOC panel supports one-click tracing back to any user request, with options to restore LLM summaries and code states during the trace. DSH's philosophy is "Everything is a Plugin," and Web interface extensions follow the same plugin mechanism. The following introduces the positioning, features, and usage of `dsh-toc-tail`. # What is it? `dsh-toc-tail` is a conversation [component] for the DeepSeek Harness Web interface.