Fix dashboard UI: correct pending color (blue) and use host_status_summary metric

agent/src/status/mod.rs

@@ -128,6 +128,21 @@ impl HostStatusManager {
         );
     }
 
+    /// Get the current host status as a metric for broadcasting to dashboard
+    pub fn get_host_status_metric(&self) -> Metric {
+        Metric {
+            name: "host_status_summary".to_string(),
+            value: cm_dashboard_shared::MetricValue::String(format!(
+                "Host aggregated from {} services", 
+                self.service_statuses.len()
+            )),
+            status: self.current_host_status,
+            timestamp: Utc::now().timestamp() as u64,
+            description: Some("Aggregated host status from all services".to_string()),
+            unit: None,
+        }
+    }
+
     /// Calculate the overall host status based on all service statuses
     fn calculate_host_status(&self) -> Status {
         if self.service_statuses.is_empty() {