dsh-meeting-cost: Meeting Cost Calculation

The `dsh-meeting-cost` plugin is maintained by uckkk and is designed to provide meeting cost calculation functionality for DSH agents. It is implemented in pure Node, has no network dependencies, and supports precise calculation based on specified parameters while returning detailed results. It allows agents to quickly assess meeting costs during conversations, making it suitable for lightweight business scenarios. Users can install it using the official command and then invoke the registered tools after installation. Because it runs with the permissions of the current process, it is recommended to review the source code and license (MIT) before use.