Gate the relay admin moderation API (/api/admin/v1) behind explicit
authentication configuration selected by BUZZ_ADMIN_AUTH: token (default),
disabled, or nip98. In nip98 mode every request carries a signed kind-27235
NIP-98 event; the authenticated pubkey resolves to an OPERATOR or MODERATOR
principal from RELAY_OPERATOR_PUBKEYS, the RELAY_OWNER_PUBKEY fallback, or the
relay_operators table. Replaces the BUZZ_ADMIN_INSECURE_NO_AUTH bypass with a
role model that is revocable without rotating a shared secret and fails closed
at every boundary.
Co-authored-by: Will Pfleger <pfleger.will@gmail.com>
Signed-off-by: Will Pfleger <pfleger.will@gmail.com>
