Re-fetches every --adblock-rules source every N seconds and atomically swaps in a rebuilt engine, so a long-lived server or MCP process tracks evolving filter lists without a restart. The value must be at least 1.

Each refresh is best-effort per source: a source that fetches cleanly replaces its own rules, while one that fails keeps its previous rules and logs an error. The process keeps serving on its prior engine.

This is an Enterprise-tier flag.