fix: Use database task counts for Completed/Failed stats on Workers page

cannaiq/src/pages/WorkersDashboard.tsx

@@ -785,6 +785,7 @@ export function WorkersDashboard() {
   const [tasks, setTasks] = useState<Task[]>([]); // Running tasks
   const [recentTasks, setRecentTasks] = useState<Task[]>([]); // Recent completed/failed
   const [pendingTaskCount, setPendingTaskCount] = useState<number>(0);
+  const [taskCounts, setTaskCounts] = useState<{ completed: number; failed: number }>({ completed: 0, failed: 0 });
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
 
@@ -820,6 +821,10 @@ export function WorkersDashboard() {
       setRecentTasks(combined.slice(0, 15));
 
       setPendingTaskCount(countsRes.data?.pending || 0);
+      setTaskCounts({
+        completed: countsRes.data?.completed || 0,
+        failed: countsRes.data?.failed || 0,
+      });
       setError(null);
     } catch (err: any) {
       console.error('Fetch error:', err);
@@ -897,8 +902,9 @@ export function WorkersDashboard() {
   const activeWorkers = workers.filter(w => w.status !== 'offline' && w.status !== 'terminated');
   const busyWorkers = workers.filter(w => w.current_task_id !== null);
   const idleWorkers = activeWorkers.filter(w => w.current_task_id === null);
-  const totalCompleted = workers.reduce((sum, w) => sum + w.tasks_completed, 0);
-  const totalFailed = workers.reduce((sum, w) => sum + w.tasks_failed, 0);
+  // Use task counts from database (survives worker restarts)
+  const totalCompleted = taskCounts.completed;
+  const totalFailed = taskCounts.failed;
 
   // Get task info for a worker
   const getWorkerTask = (workerId: string): Task | undefined => {