Unify list plugins, add solution list and per-story detail page

- vitec_usecaselist: layout + record selection like marketlist
- new plugin vitec_solutionlist (spec 7.13.3, key "solutions")
- tx_vitec_domain_model_usecase: detail_page -> resolved detailUrl
  (also gives story cards in vitec_modelcard a link for the first time)
- "Show Toolbar" checkbox on product/market/solution/usecase lists
- spec bumped to v1.9

BREAKING: vitec_productlist and vitec_usecaselist now emit an object
instead of a bare array. Consumers must read products.products and
usecases.usecases. Also found: productlist had a configurable layout
that was never serialised; it is emitted now, but keeps its own 0-3
vocabulary instead of grid/list/carousel.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

packages/vitec/Classes/UserFunc/ProductListJsonRenderer.php

@@ -152,20 +152,30 @@ class ProductListJsonRenderer
                 $productsData[] = $this->serializeProduct($product);
             }
 
+            // Envelope with layout and toolbar flag, matching the other list
+            // plugins. This turned the payload from a bare array into an object:
+            // the front end has to read `products.products` instead of
+            // iterating `products` directly. `layout` was configurable in the
+            // FlexForm all along but had never been emitted - note that product
+            // layouts are numbered 0..3 here, not the grid/list/carousel
+            // vocabulary the other lists use.
+            $response = [
+                'layout' => (string)($settings['layout'] ?? '0'),
+                'showToolbar' => (bool)($settings['showtoolbar'] ?? false),
+                'products' => $productsData,
+            ];
+
             if ($debugMode) {
-                return json_encode([
-                    'products' => $productsData,
-                    'debug' => [
-                        'pageId' => (int)($GLOBALS['TSFE']->id ?? 0),
-                        'categoryUids' => $categoryUids,
-                        'productCount' => count($productsData),
-                        'settings' => $settings,
-                        'fallbackFiles' => $this->collectFallbackFilesFromProducts($productsData),
-                    ],
-                ]);
+                $response['debug'] = [
+                    'pageId' => (int)($GLOBALS['TSFE']->id ?? 0),
+                    'categoryUids' => $categoryUids,
+                    'productCount' => count($productsData),
+                    'settings' => $settings,
+                    'fallbackFiles' => $this->collectFallbackFilesFromProducts($productsData),
+                ];
             }
 
-            return json_encode($productsData);
+            return json_encode($response);
         } catch (\Throwable $e) {
             return '';
         }