feat(widgets): forum tabs shared hot payload + terms/boards ajax

Route multi-tab forum topics through HotTopics mini/rank payload and
WidgetAjax style/plate params; wire terms/boards to real REST ajaxpager.

src/AKSRT/Widgets/WidgetForumTopicTerms.php

@@ -106,7 +106,8 @@ class WidgetForumTopicTerms extends \WP_Widget {
 			echo $args['before_title'] . esc_html($title) . $args['after_title']; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
 		}
 		// IAS-style wrap for remote refresh.
-		echo '<div class="zib-widget padding-6 aksrt-ftag-wrap">';
+		$rest = rest_url('aksrt/v1/widgets/forum-terms');
+			echo '<div class="zib-widget padding-6 aksrt-ftag-wrap ajaxpager" data-aksrt-ajaxpager data-aksrt-ajax-url="' . esc_url($rest) . '">';
 		echo $html; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
 		echo '</div>';
 		echo $args['after_widget']; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped