wrong agent to start a new invocation when last invocation was rewound

[chelxxx]

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Describe the bug
When we use rewind_async to cancel an invocation, roll back the state changes, and start a new invocation, rewound events are filtered out for LLM calls, but not when determining which agent to hand off to first.

To Reproduce
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Steps to reproduce the behavior:

1. Install '...'
2. Run '....'
3. Open '....'
4. Provide error or stacktrace

Expected behavior
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Desktop (please complete the following information):

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• Python version(python -V):
• ADK version(pip show google-adk):

Model Information:

• Are you using LiteLLM: Yes/No
• Which model is being used(e.g. gemini-2.5-pro)

Additional context
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[wuliang229]

@chelxxx could you be more specific about "not when determining which agent to hand off to first"? Maybe provide an example sequence of events or code snippet to help reproduce.