Show time and date of next meeting for every room I have access to

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Feature request

Which Nextcloud Version are you currently using: (see administration page)
Is your feature request related to a problem? Please describe.

When I look at a room where I have a event in my calendar I see when the next meeting takes place (date and time).

When I join a open room where a regular call takes place I also see it, but only the day:

On Android I can see for the same room the day and the time, same as I would have the meeting in my calendar. This is super useful for rooms and meetings I only join occasionally. In this case I don't need to have a invitation for each and every meeting but I still need to see when the next meeting takes place to be able to join.

Describe the solution you'd like

Like on Android, always show the day and the time of the next meeting. No matter if it is in my calendar or not.

Describe alternatives you've considered
Provide a clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots related to the feature request here.

No file or test is named. Start by tracing the room view that currently shows the next meeting date, then compare its behavior with the Android view described in the issue. Done means every accessible room shows both the day and time of its next regular meeting, whether or not the meeting is in the user's calendar.