[BUG] Canceling a primary registrant does not cancel guest registrations

[dwhitig]

Description

When a primary (host) registrant clicks the cancellation link in their confirmation email, only their own registration is canceled. Any guest registrations associated with that primary remain active. This can lead to inconsistent registration data and confusion for both registrants and event staff.

Steps to Reproduce

1. Register for an event as the primary registrant and add one or more guests.
2. Complete registration for both primary and guests.
3. From the confirmation email, click the cancellation link for the primary registrant.
4. Check the event’s registration list.

Expected Behavior

Canceling the primary registrant’s registration should also:

• Cancel all guest registrations associated with that primary,
  or
• Prompt the user to choose whether to cancel guests as well.

Actual Behavior

Only the primary registrant is canceled. Guest registrations remain active.

Impact

• Guests may still appear as confirmed attendees when the primary has canceled.
• Potential for no-shows and inaccurate headcount.
• Event managers may need to manually identify and cancel related guest registrations.
• Capacity will still count towards the Guests

Discussion Needed

We should determine the desired behavior:

• Option A: Automatically cancel all guest registrations when the primary is canceled.
• Option B: Prompt the primary to select which guests (if any) to cancel.
• Option C: Leave guests untouched but notify event managers.

Acceptance Criteria

• Defined cancellation behavior for guest registrations.
• Implemented logic matches agreed-upon behavior.
• Tested for edge cases (e.g., multiple guests, guests who have made payments).