Add customizable reminders set at the series or session level

Email reminders for sessions sent to everyone who is assigned to a particular session. A few criteria: - fully mobile-optimized, following existing UI patterns and tailwind theming - only editable by admins and managers - each role (participant, guardian, staff, volunteer) can be toggled off/on to fine tune who it gets sent to, defaults to all on- - for sessions that are part of a series, session reminders are inherited and controlled at the series level only and cannot be adjusted at the session level - Sessions that aren't part of a series get the same modular component for consistent UI - admins/managers can also set a reminder "in advance" time (ie 1 day before, 1 hour before, etc) with a simple just in time UI - once implemented, ensure you add this email to the table of automated emails that is shown to admins in /settings (static list, just add this to that list) - ensure this respects the org-level email on/off kill switch set in /settings like all other emails - ensure this email also follows the email template with the org name and logo in the header like all the other emails

Email reminders for sessions sent to everyone who is assigned to a particular session. A few criteria: - fully mobile-optimized, following existing UI patterns and tailwind theming - only editable by admins and managers - each role (participant, guardian, staff, volunteer) can be toggled off/on to fine tune who it gets sent to, defaults to all on- - for sessions that are part of a series, session reminders are inherited and controlled at the series level only and cannot be adjusted at the session level - Sessions that aren't part of a series get the same modular component for consistent UI - admins/managers can also set a reminder "in advance" time (ie 1 day before, 1 hour before, etc) with a simple just in time UI - once implemented, ensure you add this email to the table of automated emails that is shown to admins in /settings (static list, just add this to that list) - ensure this respects the org-level email on/off kill switch set in /settings like all other emails - ensure this email also follows the email template with the org name and logo in the header like all the other emails