Fix: Security collector debug logging + backend rebuild needed

agent/collector/security.go

@@ -3,6 +3,7 @@ package collector
 import (
 	"bufio"
 	"fmt"
+	"log"
 	"os"
 	"os/exec"
 	"regexp"
@@ -72,7 +73,12 @@ func CollectSecurity() *SecurityData {
 
 	seen := make(map[string]bool)
 	for _, path := range logFiles {
-		events := parseAuditLog(path)
+		events, err := parseAuditLog(path)
+		if err != nil {
+			log.Printf("Security: %s: %v", path, err)
+			continue
+		}
+		log.Printf("Security: %s: %d events", path, len(events))
 		for _, e := range events {
 			key := e.Timestamp + e.User + e.Source + e.Port + e.Status
 			if !seen[key] {
@@ -118,10 +124,10 @@ func CollectSecurity() *SecurityData {
 	return data
 }
 
-func parseAuditLog(path string) []LoginEvent {
+func parseAuditLog(path string) ([]LoginEvent, error) {
 	f, err := os.Open(path)
 	if err != nil {
-		return nil
+		return nil, err
 	}
 	defer f.Close()
 
@@ -166,7 +172,7 @@ func parseAuditLog(path string) []LoginEvent {
 		}
 	}
 
-	return events
+	return events, nil
 }
 
 func extractTimestamp(line string) string {