DSH Plugin: Project and Task Dual-Mode Workspace Management

The `dsh-task-runner` plugin upgrades the DSH sidebar to support a dual “Projects” and “Tasks” mode, providing independent, isolated temporary directories for ephemeral sessions. It includes a `/task` command for managing tasks (create, open, and clean up) and fixes the EAC layout to display task groups. By separating context, the tool improves the efficiency of parallel multi-task processing.