refactor(users): eliminar columna orden, listar alfabéticamente

- Migración 012: ALTER TABLE users DROP COLUMN orden
- Lookups: abogadoNames y allUsers ordenan por name ASC
- API admin: create/update_user dejan de leer/escribir orden
- UI admin: removida la columna "Orden" de la tabla y el input
  "Orden" del modal de usuario

src/Lookups.php

@@ -19,7 +19,7 @@ final class Lookups {
              WHERE activo = 1
                AND role IN ('socio','abogado')
                AND name != ''
-             ORDER BY orden ASC, name ASC"
+             ORDER BY name ASC"
         )->fetchAll();
         return array_map(fn($r) => $r['name'], $rows);
     }
@@ -43,15 +43,14 @@ final class Lookups {
      * Si $includeAdmins es false, oculta el rol admin (uso para socios).
      */
     public static function allUsers(bool $includeAdmins = true): array {
-        $sql = "SELECT id, email, name, role, activo, orden, first_seen_at, last_login_at
+        $sql = "SELECT id, email, name, role, activo, first_seen_at, last_login_at
                 FROM users";
         if (!$includeAdmins) $sql .= " WHERE role != 'admin'";
-        $sql .= " ORDER BY FIELD(role,'admin','socio','abogado','usuario'), name ASC, email ASC";
+        $sql .= " ORDER BY name ASC, email ASC";
         $rows = Db::pdo()->query($sql)->fetchAll();
         foreach ($rows as &$r) {
             $r['id']     = (int)$r['id'];
             $r['activo'] = (int)$r['activo'];
-            $r['orden']  = (int)$r['orden'];
         }
         return $rows;
     }