Settings option: enter time entries by duration only

[5TFN]

Hello, I'm happy that found this project, it looks great!

In my daily time tracking routine, I prefer to just assign a certain amount of time to a project/task and add a comment to it.
For this use case it is not necessary to set a start and end time.

It would be nice if the start/end time could be enabled/disabled with a settings option.
If disabled, the start and end time/date fields in the UI could be exchanged by just a single date field.

In the database, I see there is currently "start" and "end" in "time_entries" and I assume the duration is calculated based on that.
I guess my suggestion would require extra duration and date fields there.