Improve exception handling in ScheduledTimer and TenantTaskManager

- Add try-catch block in `ScheduledTimer` to handle exceptions without crashing application during shutdown.
- Log error messages in `TenantTaskManager` when exceptions occur

Author: sfmskywalker

src/modules/Elsa.Common/Multitenancy/EventHandlers/TenantTaskManager.cs

@@ -118,6 +118,10 @@ private async Task StartRecurringTasksAsync(ITenantScope tenantScope, ITaskExecu
                 {
                     logger.LogInformation(e, "Recurring task {TaskType} was cancelled", task.GetType().Name);
                 }
+                catch (Exception e)
+                {
+                    logger.LogError(e, "An error occurred while executing recurring task {TaskType}", task.GetType().Name);
+                }
             });
 
             _scheduledTimers.Add(timer);

src/modules/Elsa.Common/RecurringTasks/ScheduledTimer.cs

@@ -15,8 +15,24 @@ public ScheduledTimer(Func<Task> action, Func<TimeSpan> interval)
 
     private async void Callback(object? state)
     {
-        await _action();
-        _timer.Change(_interval(), Timeout.InfiniteTimeSpan);
+        try
+        {
+            try
+            {
+                await _action();
+            }
+            catch (Exception)
+            {
+                // The action failed, but we still want to reschedule the timer.
+            }
+            
+            _timer.Change(_interval(), Timeout.InfiniteTimeSpan);
+        }
+        catch (Exception)
+        {
+            // Ignore exceptions to prevent process crash (async void).
+            // This is especially important during application shutdown where the timer or dependencies might be disposed.
+        }
     }
 
     public void Dispose()