[worker] fix active tasks metric name

Author: capcom6

deployments/grafana/dashboards/worker.json

@@ -75,7 +75,7 @@
             },
             "targets": [
                 {
-                    "expr": "worker_executor_active_tasks_total",
+                    "expr": "worker_executor_active_tasks",
                     "refId": "A"
                 }
             ],

deployments/prometheus/alerts/worker-alerts.yml

@@ -11,7 +11,7 @@ groups:
           description: "Worker task error rate is {{ $value }} errors per minute, exceeding threshold"
           runbook: "Check worker logs for task failures"
       - alert: LongRunningTask
-        expr: histogram_quantile(0.95, sum(rate(worker_executor_task_duration_seconds_bucket[5m]))) > 30
+        expr: histogram_quantile(0.95, sum(rate(worker_executor_task_duration_seconds_bucket[5m])) by (le)) > 30
         for: 10m
         labels:
           severity: warning
@@ -20,7 +20,7 @@ groups:
           description: "95th percentile task duration is {{ $value }}s, above 30s threshold"
           runbook: "Review task performance and optimize if needed"
       - alert: HighActiveTasks
-        expr: worker_executor_active_tasks_total > 10
+        expr: worker_executor_active_tasks > 10
         for: 5m
         labels:
           severity: warning

internal/worker/executor/metrics.go

@@ -25,7 +25,7 @@ func newMetrics() *metrics {
 		activeTasksCounter: promauto.NewGauge(prometheus.GaugeOpts{
 			Namespace: "worker",
 			Subsystem: "executor",
-			Name:      "active_tasks_total",
+			Name:      "active_tasks",
 		}),
 		taskResult: promauto.NewCounterVec(prometheus.CounterOpts{
 			Namespace: "worker",