Fix title and description for single templates

lib/compat/wordpress-6.1/block-template-utils.php

@@ -223,7 +223,42 @@ function gutenberg_get_block_template( $id, $template_type = 'wp_template' ) {
 	$block_template->id     = $id;
 	$block_template->slug   = $slug;
 	$default_template_types = get_default_block_template_types();
-	if ( array_key_exists( $slug, $default_template_types ) ) {
+
+	$slug_parts = explode( '-', $slug, 3 );
+	if ( count( $slug_parts ) > 1 ) {
+		if ( 'single' === $slug_parts [0] ) {
+			// Get CPT labels
+			$post_type = get_post_type_object( $slug_parts[1] );
+			$labels    = $post_type->labels;
+
+			if ( count( $slug_parts ) > 2 ) {
+				// Now we look for the CPT with slug as defined in $slug_parts[2]
+				$post                  = get_page_by_path( $slug_parts[2], OBJECT, $slug_parts[1] );
+				$block_template->title = sprintf(
+					// translators: Represents the title of a user's custom template in the Site Editor, where %1$s is the singular name of a post type and %2$s is the name of the post, e.g. "Post: Hello, WordPress"
+					__( '%1$s: %2$s' ),
+					$labels->singular_name,
+					$post->post_title
+				);
+				$block_template->description = sprintf(
+						// translators: Represents the description of a user's custom template in the Site Editor, e.g. "Template for Post: Hello, WordPress"
+					__( 'Template for %1$s' ),
+					$block_template->title
+				);
+			} else {
+				$block_template->title = sprintf(
+					// translators: %s: Name of the post type e.g: "Post".
+					__( 'Single item: %s' ),
+					$labels->singular_name
+				);
+				$block_template->description = sprintf(
+					// translators: %s: Name of the post type e.g: "Post".
+					__( 'Displays a single item: %s.' ),
+					$labels->singular_name
+				);
+			}
+		}
+	} elseif ( array_key_exists( $slug, $default_template_types ) ) {
 		$block_template->title       = $default_template_types[ $slug ]['title'];
 		$block_template->description = $default_template_types[ $slug ]['description'];
 	}