Remove Docker image icon and use Status::Info

Docker images now use Status::Info like VPN IP.
No "D" prefix, no status icon - just name and metrics.
All informational sub-services handled consistently.

Version: v0.1.239

agent/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard-agent"
-version = "0.1.238"
+version = "0.1.239"
 edition = "2021"
 
 [dependencies]

agent/src/collectors/systemd.rs

@@ -152,7 +152,7 @@ impl SystemdCollector {
 
                             sub_services.push(SubServiceData {
                                 name: image_name.to_string(),
-                                service_status: self.calculate_service_status(&image_name, &image_status),
+                                service_status: Status::Info,  // Informational only, no status icon
                                 metrics,
                                 service_type: "image".to_string(),
                             });