Remind me later

[SystemKeeper]

Fixes #1313

Notes:

• On the screenshot it says 8am in all cases, but for "Later today" it's 6pm as specified and is correct in code
• Wording might change, waiting for the decision on Notify me later about this message #1313 about that, but did go with "Next Saturday" and "Next Monday" for now (CC @nimishavijay for the current state)
• When "Today" is already >= 6pm, the option is hidden
• For custom date & time the minimum selectable time would be 15 min in the future (so no reminders in the past)

[nickvergessen]

Ref nextcloud/server#39181 (comment)

[SystemKeeper]

Ref nextcloud/server#39181 (comment)

Done, updated screenshot:

[SystemKeeper]

Adjusted options as discussed:

Delete option if a reminder is already available:

[nickvergessen]

At least on the backend you could still set the reminder (it gets updated/overwritten) as well as deleting it.
According to nextcloud/server#39181 (comment) the option would be called "Clear reminder" and below that there are the normal options to set the reminder to a different value.

[SystemKeeper]

Moved to inline menu:

@nickvergessen ✅?

[nickvergessen]

swift code looks good, other code I can not understand, but seems to do it's job and screenshot is 🤩