fix(swimming): use correct column name processed_at in revenue query

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Modules/SportsActivity/Controllers/Swimming/SwimmingDashboardController.php

@@ -43,7 +43,7 @@ class SwimmingDashboardController extends Controller
                  INNER JOIN sa_groups g ON g.id = gp.group_id
                  INNER JOIN sa_programs p ON p.id = g.program_id
                  WHERE p.discipline_id = ? AND pr.status = 'completed'
-                 AND pr.completed_at BETWEEN ? AND ?) as revenue_this_month
+                 AND pr.processed_at BETWEEN ? AND ?) as revenue_this_month
         ", [$disciplineId, $disciplineId, $disciplineId, $disciplineId, $monthStart . ' 00:00:00', $monthEnd . ' 23:59:59']);
 
         $groups = $db->select("