All fire-and-forget DB workers on IntruderScreen now use exit_on_error=False.
cancel_node() is async-cooperative and doesn't cancel immediately — switch_db()
could close the connection before the worker's next await, causing
ValueError/ProgrammingError that crashed the whole TUI as FATAL EXCEPTION.

Full changelog: https://github.com/DrXOps/pentool/compare/v0.2.10...v0.2.11