Fix stale alerts for deleted agents on command deck

server/internal/api/fleet_handler.go

@@ -522,6 +522,11 @@ func (f *FleetHandler) DeleteAgent(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "delete failed: "+err.Error(), http.StatusInternalServerError)
 		return
 	}
+	// Clear stale in-memory alerts so the machine stops showing up in the
+	// dashboard alert banner after deletion.
+	if f.alerts != nil {
+		f.alerts.ClearAgent(id)
+	}
 	w.Header().Set("Content-Type", "application/json")
 	json.NewEncoder(w).Encode(map[string]bool{"success": true})
 }
@@ -543,6 +548,9 @@ func (f *FleetHandler) BulkDeleteAgents(w http.ResponseWriter, r *http.Request)
 		}
 		if err := f.db.DeleteAgent(id); err == nil {
 			deleted++
+			if f.alerts != nil {
+				f.alerts.ClearAgent(id)
+			}
 		}
 	}
 	w.Header().Set("Content-Type", "application/json")