Add support for recurring cards and tasks

Hi!

It would be helpful to support recurring cards or recurring tasks in Nextcloud Deck:
Users should be able to configure a card so that it is recreated or rescheduled automatically according to a defined recurrence rule.

For example:

• Every month on the 15th
• Every Monday
• Every two weeks
• On the first working day of each month
• Annually on a specific date

Expected behavior: When creating or editing a card, users should be able to define:

• A recurrence frequency
• A recurrence interval
• A due date or time
• An optional end date
• Whether the existing card should be reused or a new card should be created for each occurrence

For example, a card configured as “Due on the 15th of every month” could automatically create the next occurrence once the current card is completed, or create all upcoming occurrences according to the selected recurrence rule.

Possible options: A recurring card could be generated:

• When the previous occurrence is marked as completed
• A defined number of days before the next due date
• Automatically for a configurable number of future occurrences

It would also be useful to preserve selected card properties, such as:

• Stack
• Assigned users
• Labels
• Description
• Checklist
• Attachments
• Estimated effort

Use cases

• Monthly administrative tasks
• Regular maintenance and system checks
• Weekly team routines
• Recurring reporting deadlines
• Periodic reminders and organizational tasks

Is support for recurring cards or recurring due dates already planned or being considered?

Thank you!

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The issue names no files, tests, or entry points. Start by reviewing the existing card creation, editing, due-date, and completion flows in Nextcloud Deck, then clarify the recurrence model and generation rules with maintainers. Done would require an agreed, tested implementation covering the requested recurrence options and preserved card properties.