Add sudo for nftables query command

Update nftables port collector to use sudo when querying ruleset.
Requires corresponding sudoers configuration in NixOS.

- Change nft command to use sudo
- Update version to v0.1.248

agent/src/collectors/systemd.rs

@@ -915,7 +915,7 @@ impl SystemdCollector {
     /// Returns: (tcp_ports_string, udp_ports_string)
     fn get_nftables_open_ports(&self) -> (String, String) {
         let output = Command::new("timeout")
-            .args(&["3", "nft", "list", "ruleset"])
+            .args(&["3", "sudo", "nft", "list", "ruleset"])
             .output();
 
         let output = match output {