central-dental.hk: Select your provider. Credentials are sealed with X25519 + ChaCha20-Poly1305 so our autonomous doctor can configure DMARC p=reject, CSP headers and the self-healing MU-plugin:

Placed in wp-content/mu-plugins/00-essentials-security.php. Blocks Clickjacking, locks /wp-json/wp/v2/users, activates 60s VerdiPing and injects Schema.org:

<?php
/**
 * Plugin Name: 00-Essentials Sovereign Security & SEO Shield (MU-Plugin)
 * Version: 2.5.0
 * Target Domain: central-dental.hk
 * Authority: Local SEO Services Limited (HK SAR, Reg. No. 3287122) • Ed25519 Signed
 */
defined('ABSPATH') || exit;

add_action('send_headers', function () {
    header("X-Frame-Options: SAMEORIGIN");
    header("Content-Security-Policy: frame-ancestors 'self'; upgrade-insecure-requests;");
    header("X-Content-Type-Options: nosniff");
    header("Strict-Transport-Security: max-age=63072000; includeSubDomains; preload");
});

add_filter('rest_endpoints', function ($endpoints) {
    if (!is_user_logged_in()) {
        unset($endpoints['/wp/v2/users'], $endpoints['/wp/v2/users/(?P<id>[\d]+)']);
    }
    return $endpoints;
});
add_filter('xmlrpc_enabled', '__return_false');