- Store direct reference to SecurityMiddleware instance in app.state._security_middleware
immediately at module load time in main.py (before middleware_stack is built)
- Rewrite conftest.py _reset_all() to use app.state._security_middleware instead of
fragile middleware stack traversal that failed before the first request was made
- Set explicit client=('127.0.0.1', 50000) on ASGITransport across all test files
to ensure guard-core always sees a valid IP and can ban/track it correctly