(agents/mcp-servers) accept "auth" option supporting either IAM or Cognito

[cogwirrel]

Description

Add an auth option to the ts/py agent/mcp server generators. This should accept the same IAM or Cognito options as the API generators accept.

This should vend CDK constructs which are specific to the auth method selected.

Motivation

• Consistency with our api generators, saving a little time when you know your auth method
• Setup for connection generators to support agents/mcp servers given the auth method is known

One step towards the wider agent connection feature: #326

Suggested Implementation

• Ensure vended CDK/Terraform is specific to the auth method selected
• Add the auth option to the component metadata in project.json so that it can be read by the connection generator later
• Ensure that we add the agent core runtime arn to runtime config, under eg agentRuntimes.<my-agent>

Contribute to feature

• I'd be willing to implement this feature