feat: Add hostname resolution to Nmap scans

- Add -R flag to Nmap scan options to enable reverse DNS lookup.
- Modify the Nmap processing logic to extract and store hostnames.
- Update PROGRESS.md to reflect the completion of the task.

monitor_agent.py

@@ -171,6 +171,7 @@ def get_nmap_scan_results():
                 host_info = {
                     "ip": host,
                     "status": scan_data.get("status", {}).get("state", "unknown"),
+                    "hostname": scan_data.get("hostnames", [{}])[0].get("name", ""),
                     "open_ports": []
                 }
                 if "tcp" in scan_data: