Can an agent interact without going through the hostAgent?

### What happened?

Can an agent interact without going through the hostAgent? From what I can see in the code, the hostAgent assigns tasks to the remote agent and executes operations by treating the remote agent and the operations as tools. Are there other ways to orchestrate agents without going through the hostAgent?

### Relevant log output

```shell

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### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

Review the A2A protocol documentation and the codebase to understand the agent orchestration architecture. Look for examples of direct agent-to-agent communication or alternative orchestration patterns. Determine if the hostAgent is mandatory or if there are bypass mechanisms documented or implemented.

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