bug: edit task

It seems that there is an issue with your "edit task" functionality where it creates a new input for subtasks every time it is clicked. Additionally, even if the subtask input is empty, it still appears in the task preview.

- [ ] Review the code responsible for generating the subtask inputs when "edit task" is clicked. Make sure that it only creates a new input if necessary, such as when there are existing subtasks or a specific condition is met.
- [ ] Before creating a new subtask input, check if the previous input is empty. If it is empty, you can consider removing it or skipping the creation of a new input altogether.
- [ ] Ensure that the task preview rendering logic is updated accordingly. It should only display subtasks that have valid content, filtering out any empty subtasks.