POST /members/invites was returning the full ApiResponseInviteResponse
wrapper. The client set activeInvite directly from the response body,
so shareUrl/inviteCode/expiresAt were missing (nested under .data).
Fixed to return data?.data — the inner InviteResponse — matching the
shape that InvitePanel and page.server.ts already expect.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
