Fix 10 HIGH integer comparisons in backup/maintenance/security modules

FIXES:
enable-cphulk.sh:
- Line 234: $file_ip_count → ${file_ip_count:-0}
- Line 333: $FAILED → ${FAILED:-0}

cleanup-toolkit-data.sh:
- Line 209: $cleaned_size → ${cleaned_size:-0} (3 instances)
- Line 236: $missing → ${missing:-0}

acronis-update.sh:
- Line 229: $UPGRADE_EXIT_CODE → ${UPGRADE_EXIT_CODE:-0}

acronis-install.sh:
- Line 301: $INSTALL_EXIT_CODE → ${INSTALL_EXIT_CODE:-0}

acronis-logs.sh:
- Line 64: $log_count → ${log_count:-0}
- Line 215: $old_logs → ${old_logs:-0}

IMPACT:
- Prevents errors in backup/maintenance scripts
- Safe defaults for all exit code checks
- More robust error handling

PROGRESS:
- Fixed 57+ integer comparison issues total
- Only 3 HIGH issues remaining!
- Total issues: 23 (was 41 originally)

modules/backup/acronis-install.sh

@@ -298,7 +298,7 @@ echo -e "${DIM}─────────────────────
 echo ""
 
 # Check installation result
-if [ $INSTALL_EXIT_CODE -eq 0 ]; then
+if [ "${INSTALL_EXIT_CODE:-0}" -eq 0 ]; then
     print_success "Installation completed successfully!"
     echo ""