dsh-weekly-plan: Volume Planning

The DSH ecosystem emphasizes extending agent capabilities through plugins. `dsh-weekly-plan` is a locally executed running plan workflow plugin implemented in pure Node.js and does not depend on network interfaces. It dynamically generates specific running training plans based on input parameters and is maintained and open-sourced by uckkk. Users can install it with the official command and invoke the `weekly_plan` tool in conversations or workflows to retrieve plans. Because it runs with DSH process privileges, users are advised to review the source code and license before installation.