- Create logged_task() helper in backend/app/utils/async_utils.py to wrap
fire-and-forget coroutines with exception logging
- Ensures unhandled task exceptions are always logged to structlog instead of
silently discarded (Python 3.11+ RuntimeWarning)
- Update ban_service.py to use logged_task() for geo_cache.lookup_batch()
background resolution
- Add comprehensive tests for logged_task() in test_async_utils.py
- Document fire-and-forget task conventions in Backend-Development.md
The logged_task() wrapper catches any exception raised in a background task,
logs it with full traceback context and task name, and never re-raises.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>