Enforce a millions-strong external IP blocklist in-app so the OS firewall
never has to hold it (Windows BFE can't). FileBlocklist loads a versioned
file into an immutable SortedRangeIndex snapshot off the game loop (yields to
world saves) and swaps it atomically; the accept path gates against it after
the manual-ban check and, once per suppression window (PromotedGuard),
promotes the hit to CrowdSec (scenario modernuo/blocklist) so the OS bouncer
kernel-drops repeat traffic. The bulk list is produced entirely out-of-process.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
