fix: adding circles to events (#6023)

[MrAn0nym]

ContactController::getCircleMembers is used to fetch all members of a circle, when adding that circle to an event.

Currently the function assumes members to be a nextcloud user:

calendar/lib/Controller/ContactController.php

Lines 227 to 229 in 04e8e49

	$circleMemberUserId = $circleMember->getUserId();
	$user = $this->userManager->get($circleMemberUserId);

This results in empty return values, which in turn causes an error and results in no member of the circle being added

calendar/lib/Controller/ContactController.php

Lines 231 to 233 in 0a0dc23

	if ($user === null) {
	throw new ServiceException('Could not find organizer');
	}

The PR changes the code to handle all types separately. Whilst this is not perfect and problems like federation or auto-updating memberlists are not solved by this it at least provides a short term fix for #6023 #6485 and one aspect of nextcloud/circles#1690 if I'm not mistaken.

[MrAn0nym]

Didn't manage to look into how one would write tests yet and I believe php-cs-fixer will at least replace some quotes as well. If anyone else has the time to fix those last steps feel free to do so, otherwise I'll do so when I get around

[SebastianKrupinski]

Hi @MrAn0nym

Thank you for the PR.

FYI, you might want to wait a couple weeks for this, as there are some pending changes that will be applied to the contacts controller which might effect your work.