## FRE-4500: Cross-Service Alert Correlation - Implemented `@shieldai/correlation` package with AlertNormalizer, CorrelationEngine, CorrelationService - Added NormalizedAlert and CorrelationGroup Prisma models - Extended Severity enum (LOW, INFO, MEDIUM, WARNING, HIGH, CRITICAL) - Added AlertSource, AlertCategory, CorrelationStatus, EntityType enums - Created correlation API routes at /api/v1/correlation/ - Wired DarkWatch, SpamShield, VoicePrint services to emit normalized alerts - Correlation package builds successfully (tsc --noEmit) - Marked issue as in_review - Commit: 03276dd