Change docker image display format and status

Changes:
- Rename docker images from 'image_node:18...' to 'I node:18...' for conciseness
- Change image status from 'active' to 'inactive' for neutral informational display
- Images now show with gray empty circle ○ instead of green filled circle ●

Docker images are static artifacts without meaningful operational status, so using inactive status provides neutral gray display that won't trigger alerts or affect service status aggregation.

Cargo.lock

@@ -279,7 +279,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.187"
+version = "0.1.188"
 dependencies = [
  "anyhow",
  "chrono",
@@ -301,7 +301,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.187"
+version = "0.1.188"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -324,7 +324,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.187"
+version = "0.1.188"
 dependencies = [
  "chrono",
  "serde",

agent/src/collectors/systemd.rs

@@ -865,8 +865,8 @@ impl SystemdCollector {
                 let size_mb = self.parse_docker_size(size_str);
 
                 images.push((
-                    format!("image_{}", image_name),
-                    "active".to_string(), // Images are always "active" (present)
+                    format!("I {}", image_name),
+                    "inactive".to_string(), // Images are informational - use inactive for neutral display
                     size_str.to_string(),
                     size_mb
                 ));