Fix 'Clear Completed' to return to previous module when queue is empty

When 'Clear Completed' empties the queue, return to the previous
module instead of staying in an empty queue view. If jobs remain
after clearing, stay in queue view and refresh.

main.go

@@ -1121,7 +1121,17 @@ func (s *appState) refreshQueueView() {
 		func() { // onClear
 			s.jobQueue.Clear()
 			s.clearVideo()
-			s.refreshQueueView() // Refresh
+
+			// If queue is now empty, return to previous module
+			if len(s.jobQueue.List()) == 0 {
+				if s.lastModule != "" && s.lastModule != "queue" {
+					s.showModule(s.lastModule)
+				} else {
+					s.showMainMenu()
+				}
+			} else {
+				s.refreshQueueView() // Refresh if jobs remain
+			}
 		},
 		func() { // onClearAll
 			s.jobQueue.ClearAll()