Improve MCP server support

[paulyuk]

There is a commented out section of code showing optional ability to run the agent with MCP server tools passed in. It is not correct.

Please update this sample in simplest possible way to enable remote MCP servers to pass in their tools to the agent. use the learn example from this document: https://learn.microsoft.com/en-us/agent-framework/user-guide/model-context-protocol/using-mcp-tools?pivots=programming-language-python