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/Configuration/Sets/Vitecset/setup.typoscript

@@ -113,6 +113,18 @@ tt_content {
         }
     }
 
+    vitec_solutionlist < lib.contentElementWithHeader
+    vitec_solutionlist {
+        fields {
+            content {
+                fields {
+                    solutions = USER
+                    solutions.userFunc = Evomedien\Vitec\UserFunc\SolutionListJsonRenderer->render
+                }
+            }
+        }
+    }
+
     vitec_solutionshow < lib.contentElementWithHeader
     vitec_solutionshow {
         fields {