Use "Due date" as implicit "Threshold date" for sorting

[AlphaLEXray]

I don't know if this qualifies for a "feature request" so I started this discussion.

When having the "Threshold date" above the "Due date" in the sorting priority every task without a "Threshold date" is sorted below those with one. This leads to tasks due today being eclipsed by tasks due later.

Example:

Example tasks:

Task 1 due:2023-12-03
Task 2 due:2023-12-24 t:2023-12-10
Task 3 due:2023-12-07 t:2023-12-05

Sorting order

• Threshold date
• Due date

Current order:

Task 3 due:2023-12-07 t:2023-12-05
Task 2 due:2023-12-24 t:2023-12-10
Task 1 due:2023-12-03

Proposed order:

Task 1 due:2023-12-03 (t:2023-12-03 - implicit Threshold date)
Task 3 due:2023-12-07 t:2023-12-05
Task 2 due:2023-12-24 t:2023-12-10

As one can see in the example above the task, which is due earlier is "outranked" by the tasks with a threshold date. When the due date is used as an implicit threshold date this is not the case any more.