Recurring email blast schedules

Let admins create recurring email blast schedules (e.g. weekly volunteer digest, monthly upcoming sessions) that auto-send on a cadence. Schedules are managed in a dedicated Recurring tab; the blasts they generate appear in the main Blasts list like any other blast, so there's one place to see all email activity.

Let admins create recurring email blast schedules (e.g. weekly volunteer digest, monthly upcoming sessions) that auto-send on a cadence. Schedules are managed in a dedicated Recurring tab; the blasts they generate appear in the main Blasts list like any other blast, so there's one place to see all email activity.