Handle change of date in a tracked work entry when project assignment is no longer valid on the new date

[katariniss]

I as a product owner
Want to work out the scenario when a work entry is being edited but on the new date there is no project associated with the tracked task
So that we knew how to handle this case

Steps:

1. An employee tracks a task under a chosen project, e.g. Jan 15, 2026
2. Next day he wants to edit this task to change the date, e.g. Jan 18, 2026
3. On Jan 18 there is no project he wants to log this task under, because his assignment to this project ended on Jan 17, 2026

We need to think if we want to clear what was already filled in the Project field or handle this situation some other way, before we start to implement real projects list.