feat: caching, optimization, legal pages & footer

- WP Super Cache enabled (PHP mode, gzip, Nginx compatible)
- Autoptimize: CSS/HTML minification + deferred JS + Google Fonts optimization
- Cookie Notice: GDPR/LOPD banner styled with brand colors (navy/burgundy/gold)
- Legal pages: Aviso Legal, Política de Privacidad, Política de Cookies (ES)
- MU-plugin: custom footer with legal links + Cloud Host credit
- Footer: copyright, legal nav, Hosted & Maintained by Cloud Host (cloudhost.es)
- Security: X-Frame-Options, X-Content-Type, Referrer-Policy headers
- Security: XML-RPC disabled, REST user enumeration blocked
- Performance: emoji scripts removed, post revisions limited to 3

wp-content/plugins/wp-super-cache/inc/preload-notification.php

@@ -0,0 +1,30 @@
+<?php
+
+// phpcs:disable WordPress.Security.NonceVerification.Recommended
+
+function wpsc_preload_notification_scripts() {
+	if (
+		isset( $_GET['page'] ) && $_GET['page'] === 'wpsupercache' &&
+		isset( $_GET['tab'] ) && $_GET['tab'] === 'preload'
+	) {
+		wp_enqueue_script(
+			'preload-notification',
+			plugins_url( '/js/preload-notification.js', __DIR__ ),
+			array( 'jquery', 'wp-i18n' ),
+			WPSC_VERSION_ID,
+			true
+		);
+
+		wp_localize_script(
+			'preload-notification',
+			'wpsc_preload_ajax',
+			array(
+				'ajax_url'       => admin_url( 'admin-ajax.php' ),
+				'nonce'          => wp_create_nonce( 'wpsc-get-preload-status' ),
+				'preload_status' => wpsc_get_preload_status( true ),
+			)
+		);
+	}
+}
+
+add_action( 'admin_footer', 'wpsc_preload_notification_scripts' );