* test: add unit tests for TodoMiddleware
Cover context-loss detection logic:
- _todos_in_messages and _reminder_in_messages helpers
- _format_todos formatting
- Reminder injection when write_todos truncated
- No-op when todos visible or reminder already present
- abefore_model async delegation
* test: fix event loop error in todo middleware async test
Use asyncio.run() instead of get_event_loop().run_until_complete()
to avoid RuntimeError on Python 3.12 where no default event loop
exists in the main thread.
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
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