Admin page for a single CRM contact list's memberships — paginated member table (status/source/email, remove action) plus a manual add-by-email form.
The add form always creates a brand-new contact (Lists.add_new_contact_to_list/3),
matching the import engine's policy — except when the typed email already
holds a "removed" slot in this list (idx_crm_list_members_list_email),
in which case a new-contact insert would just fail. That case gets its own
"Resubscribe" affordance instead: reactivates the EXISTING contact's
membership (Lists.add_contact_to_list/3) rather than trying (and
failing) to create a second contact for the same email. Resubscribe never
touches the found contact's name/locale — only the membership.