Update version of @artinet/agent-relay-mcp to 0.0.5 and dependencies in package.json and package-lock.json

- Incremented version of @artinet/sdk to ^0.5.18, @artinet/types to ^0.0.8, and @artinet/agent-relay to ^0.0.8.
- Updated @modelcontextprotocol/sdk to ^1.20.1.
- Refactored sendMessage, getTask, and cancelTask method calls in server.ts for improved parameter structure.
- Added tags to test agent card in server.test.ts.

Author: EditUndo