feat: page banners use the page's Featured Image when set

- Theme design pages (About, Contact, FAQ, blog list) use the page's Featured
  Image (Posts page for the blog) and fall back to the design photo; no teal
  tint over a custom image
- Plugin hero (homepage [viator_hero], [viator_listing] pages) prefers the
  hosting page's Featured Image over the Settings hero image
- Theme 1.0.12, plugin 1.9.4

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

viator-collector/includes/helpers.php

@@ -141,13 +141,21 @@ function vc_hero_image_url() {
 /**
  * Hero image *source* for the current view: an attachment ID when available
  * (so it can be rendered responsively), otherwise a URL. Resolution order:
- *   1. On a term archive, that term's own image.
- *   2. The "Hero image" chosen in Settings (attachment ID preferred).
- *   3. Nothing.
+ *   1. On a page (e.g. the homepage hosting [viator_hero]), its Featured Image.
+ *   2. On a term archive, that term's own image.
+ *   3. The "Hero image" chosen in Settings (attachment ID preferred).
+ *   4. Nothing.
  *
  * @return int|string Attachment ID, image URL, or '' .
  */
 function vc_hero_image_source() {
+	if ( is_singular() && ! is_singular( 'viator_tour' ) ) {
+		$thumb = (int) get_post_thumbnail_id( get_queried_object_id() );
+		if ( $thumb ) {
+			return apply_filters( 'vc_hero_image_source', $thumb );
+		}
+	}
+
 	if ( is_tax( array( 'viator_destination', 'viator_tag', 'viator_category' ) ) ) {
 		$term = get_queried_object();
 		if ( $term && ! is_wp_error( $term ) ) {