feat(crowdsec): Fix threat stats and add bouncer effectiveness dashboard
- Fix top_scenarios parsing from cscli metrics (CAPI blocklist breakdown)
- Add bouncer stats: dropped packets/bytes, processed packets/bytes, active bans
- Update overview.js with threat types visualization (bar charts + percentages)
- Show real stats: Active Bans, Blocked Packets, Blocked Traffic
- Add CSS for threat type icons, progress bars, and severity colors
- Parse CAPI decisions table: ssh:bruteforce, ssh:exploit, generic:scan, tcp:scan
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>