plugins: scaffold bui-themer plugin

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/app/package.json

@@ -46,6 +46,7 @@
     "@backstage/integration-react": "workspace:^",
     "@backstage/plugin-api-docs": "workspace:^",
     "@backstage/plugin-auth-react": "workspace:^",
+    "@backstage/plugin-bui-themer": "workspace:^",
     "@backstage/plugin-catalog": "workspace:^",
     "@backstage/plugin-catalog-common": "workspace:^",
     "@backstage/plugin-catalog-graph": "workspace:^",

packages/app/src/App.tsx

@@ -73,6 +73,7 @@ import {
 } from '@backstage/plugin-notifications';
 import { CustomizableHomePage } from './components/home/CustomizableHomePage';
 import { HomePage } from './components/home/HomePage';
+import { BuiThemerPage } from '@backstage/plugin-bui-themer';
 
 const app = createApp({
   apis,
@@ -208,6 +209,7 @@ const routes = (
       {customDevToolsPage}
     </Route>
     <Route path="/notifications" element={<NotificationsPage />} />
+    <Route path="/bui-themer" element={<BuiThemerPage />} />
   </FlatRoutes>
 );