dsh-sctrk: DeepSeek Harness (DSH) Session Trace Bar

dsh-sctrk is a visual session trajectory plugin for DeepSeek Harness. Using an 8px floating rail on the right, it maps long-session nodes to a color scale and automatically aggregates dense nodes into gradient cluster dots. Users can hover to preview nodes or click/drag the rail for precise jumps and proportional scrolling. The plugin is MIT licensed, supports theme adaptation, is easy to install, and is designed to address the difficulty of navigating long sessions.