New email address and invitation delivery

For GiveCampus accounts and administrator access.

The consolidated fundraising-admin creation flow sends an invitation to the administrator email and links an existing confirmed user when that email matches. The list exposes Resend Invite for Not Registered entries. Confirm the intended email and saved administrator record before resending; an invitation notification being queued is not proof of delivery. Avoid creating multiple identities just to work around a school SSO email mismatch.