feat(user-center): deepen zibll parity and profile media

inc/helpers/user-center-renderers/sidebar-stats.php

@@ -24,9 +24,11 @@ defined('ABSPATH') || exit;
 				<span class="uc-stats__label"><?php echo esc_html($dashboard_tabs[$stat_tab]['label']); ?></span>
 			</a>
 		<?php endforeach; ?>
+		<?php if (!empty($messages_url)) : ?>
 		<a class="uc-stats__item" href="<?php echo esc_url($messages_url); ?>">
 			<span class="uc-stats__value"><?php echo esc_html((string) $notification_unread_count); ?></span>
 			<span class="uc-stats__label"><?php esc_html_e('通知', 'aksrt'); ?></span>
 		</a>
+		<?php endif; ?>
 	</div>
 </div>