Add detailed error logging for nft command failures

- Log exit status code when nft command fails
- Log stderr output to diagnose issues
- Distinguish between command execution failure and non-zero exit
- Update version to v0.1.253

agent/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard-agent"
-version = "0.1.252"
+version = "0.1.253"
 edition = "2021"
 
 [dependencies]

agent/src/collectors/systemd.rs

@@ -920,8 +920,13 @@ impl SystemdCollector {
 
         let output = match output {
             Ok(out) if out.status.success() => out,
-            _ => {
-                info!("Failed to run nft list ruleset");
+            Ok(out) => {
+                info!("nft command failed with status: {:?}, stderr: {}",
+                    out.status, String::from_utf8_lossy(&out.stderr));
+                return (String::new(), String::new());
+            }
+            Err(e) => {
+                info!("Failed to execute nft command: {}", e);
                 return (String::new(), String::new());
             }
         };