Fix stall warning spam in ClamAV scanner

Bug: Stall warning was logging every 0.2s after reaching 60s threshold
Fix: Changed >= to == so it only logs once when counter hits 300

Before: if [ stall_counter -ge 300 ]  (fires forever)
After:  if [ stall_counter -eq 300 ]  (fires once)

modules/security/malware-scanner.sh

@@ -969,7 +969,7 @@ for scanner in "${AVAILABLE_SCANNERS[@]}"; do
                     # Check for stalled scan (no log growth in 60 seconds)
                     if [ "$current_size" -eq "$last_size" ]; then
                         stall_counter=$((stall_counter + 1))
-                        if [ $stall_counter -ge 300 ]; then  # 60 seconds (300 * 0.2s)
+                        if [ $stall_counter -eq 300 ]; then  # 60 seconds (300 * 0.2s) - log only once
                             log_message "WARNING: ClamAV scan appears stalled (no activity for 60s)"
                         fi
                     else