Add support for MCP Tools for Foundry Agents

[markwallace-microsoft]

Foundry (aka Persistent) Agents now support a MCP tool type and we need to support this in AF. Likely this will required M.E.AI changes to support the new AITool type.

Python PR for SK: microsoft/semantic-kernel#12736

[stephentoub]

dotnet/extensions#6492

[rogerbarreto]

Closing this issue as this is being handled via the Epic

• Create representations for hosted MCP servers and content dotnet/extensions#6492