feat(accounts): implement birthday prop

[st3iny]

• Resolves: #

Summary

cc @szaimen@JohannesGGE

TODO

• bug: reloading does not show new and set birthday
• other todo comments

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[szaimen]

todo: should not duplicate the debounce logic

[szaimen]

Unfortunately Richard and me did not succeed in publishing the birthday calendar to the calendar app yet.

There are two ways how this could be accomplished in theory that we thought about:

1. Making the system birthday calendar publicly available by sharing it with each user and rewriting the whole logic around the personal birthday calendar in order to merge it into the system birthday calendar
2. Making the system birthday calendar available by sharing it with each user and couple it in the frontend to the personal birthday calendar and always hide it from the list - so that if the birthday calendar gets deactived, the system birthday calendar also get disabled hidden which is probably the best solution to the problem.

[tcitworld]

2. looks the best one…until you get some user that wants their personal birthday calendar but not the system birthday calendar

Another (more complex) possibility is to have something like nextcloud/calendar#4453. You would manually pick addressbooks you want to consider for the birthday calendar, including the system one.

[st3iny]

Yeah, well that would be a great extension. The complexity of the second option is already high enough for my liking. We will try to have another look at the feature if time permits.

[szaimen]

I guess this can be closed now that #45512 was merged?

[st3iny]

True. Your and Thomas' comment from earlier are worthy of archiving if anyone ever picks up the birthday calendar feature again.

[aurisnoctis]

True. Your and Thomas' comment from earlier are worthy of archiving if anyone ever picks up the birthday calendar feature again.

Does this mean that #45512 does not cover integrating the birthdays into a calendar that everyone can see / subscribe to?

[st3iny]

Yes, there is currently no system-wide birthday calendar for users. This is very hard to implement correctly and the reasons are stated above.