feat(web): /search two-pane screen (debounced query, visibility filter, load more) + nav

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/src/app.tsx

@@ -7,6 +7,8 @@ import { AppShell } from "./shell/app-shell";
 import { ObjectsPage } from "./objects/objects-page";
 import { ObjectDetail } from "./objects/object-detail";
 import { SelectPrompt } from "./objects/select-prompt";
+import { SearchPage } from "./search/search-page";
+import { SelectSearchPrompt } from "./search/select-search-prompt";
 import { VocabulariesPage } from "./vocab/vocabularies-page";
 import { VocabularyTerms } from "./vocab/vocabulary-terms";
 import { SelectVocabularyPrompt } from "./vocab/select-vocabulary-prompt";
@@ -55,6 +57,10 @@ export function App() {
               <Route index element={<SelectVocabularyPrompt />} />
               <Route path=":id" element={<VocabularyTerms />} />
             </Route>
+            <Route path="/search" element={<SearchPage />}>
+              <Route index element={<SelectSearchPrompt />} />
+              <Route path=":id" element={<ObjectDetail />} />
+            </Route>
             <Route path="/authorities" element={<Navigate to="/authorities/person" replace />} />
             <Route path="/authorities/:kind" element={<AuthoritiesPage />} />
             <Route path="/" element={<Navigate to="/objects" replace />} />