[Enhancement] Prevent empty tasks and treat empty edit as delete with undo

[kodebarista]

Issue/Description:
Currently, the app allows creating tasks with no text (just space) sub-tasks with no char at all and saving existing tasks as empty. This leads to meaningless entries. Additionally, if a user accidentally clears text during edit (e.g., via the "X" button), there is no way to recover what was typed, resulting in an empty task.

Steps to Reproduce:

• Open Tasks app
• Create a new task with just space & create
• Observe an empty task being created
• Edit an existing task with valid text
• Clear all text (e.g., using the "X" button) and save
• Observe the task becomes empty with no recovery option

Expected Behavior:

• Creating a new task with no text should be discarded (no task created on Enter).
• Creating a new sub-task with no text should be discarded
• Editing an existing task:
  • If text becomes empty and is saved, it should trigger a delete action instead of saving an empty task.
  • The delete action then trigger undo, allowing the user to restore the task to original text (before edit).

Other Notes:
This change would prevent accidental creation of empty tasks and provide a safer editing experience by enabling recovery through undo or trash.

• tasks & sub-tasks with no meaningful information

[edfloreshz]

This is an easy fix! I'm simply checking that the input is not empty, I should also check for white spaces.

[kodebarista]

Yeah, trimming before check should fix this