Fix issue 946

[Misiu]

Using Claude Opus I was able to trace down the issue and fix it.

When in scheme mode, we don't need to be able to uncheck the end time, because the blocks should fill the entire day.
I've tested the changes on 3 systems that I'm administering and everything seems to work.

I'm preparing other PR's, but first I'd like to fix this.

Fixes #946

[nielsfaber]

Thanks for helping out! The refered issue has been open for a while, i had/chose to prioritize other issues.

When in scheme mode, we don't need to be able to uncheck the end time, because the blocks should fill the entire day

The checkbox was for end time intended as a feature for users who wanted 1 minute tasks in the same way as with the single mode editor. But I agree that maybe it introduces only confusion and complexity, so maybe its better to remove it indeed.

How does your PR handle the toggling between the scheme mode and single mode? Are users able to switch back and forth without the schedule being modified?

[Misiu]

Hi Niels, I fully agree this isn't that important, but want to give it a try.
I just created a new single mode schedule, then switched to scheme mode.

Basically, it created a single 1-minute slot, but I'm not sure if this is correct.

When in single mode, you just set the time when a specific action must take place, in my base open cover at 2PM, but in scheme mode you should create a whole scenario, so if I want to have a scheduler for covers I should add one slot lets say from 2-4PM with open action, and for the rest (first and last blocks) it should be closed.

I can try to make this PR smaller if you like, but I need some guidence on the direction :)

[nielsfaber]

Looks good to me. Thanks again! 👍