Add a two-dimensional grid / an array of time and location/duty

[stefan123t]

⚠️ This issue respects the following points: ⚠️

• I agree to follow Nextcloud's Code of Conduct.

Describe the goal you'd like to achieve

As a poll owner, I want to be able to add a two-dimensional poll, because it helps to assign duties for e.g. a small festival at a school, etc.

Describe possible solutions

So for multiple times there are multiple options or a list of options to choose from.
Ideally you can specify the max number of votes/assignees per duty.

time	option 1	option 2	option 3	...	option N
time1 11:00 - 12:30	votes[1/1]	votes[2/1]	votes[3/1]	...	votes[N/1]
time2 12:30 - 14:00	votes[1/2]	votes[2/2]	votes[3/2]	...	votes[N/2]
...	...	...	...	...	...
timeM 15:30 - 16:00	votes[1/M]	votes[2/M]	votes[3/M]	...	votes[N/M]

Top-down should be time of day
left-right should be the order of the duties by default

Caveat: there may be a different list of duties per time of day.

But the two axis could be switched if necessary / wanted for display purpose.
An additional plus would be to filter on a specific duty option / time row/column.

Additional context

I got the idea from a tool in german: www.standeinteilung.de

Here is an example from the setup & configuration screen

[dartcafe]

Although I like this idea, I would call it a new app idea but a new polls feature. I fear, you will not find that in polls in the near future.

There will be a lot of work to do this, because from the point, I can think about a lot of user stories making this feature/app valuable. I will keep it in my mind, but it will break a lot of of Poll's concepts and would raise the app's complexity significatially.