Navigation: Integrate search into topnav (#54925)

* behaviour mostly there

* slight performance improvement

* slightly nicer...

* refactor search and add it to the store

* add comments about removing old component

* remove unneeded logic

* small design tweak

* More small tweaks

* Restore top margin

* add onCloseSearch/onSelectSearchItem to useSearchQuery

Co-authored-by: Torkel Ödegaard <torkel@grafana.com>

public/app/features/dashboard/components/DashboardSettings/DashboardSettings.test.tsx

@@ -16,6 +16,7 @@ import { DashboardSettings } from './DashboardSettings';
 jest.mock('@grafana/runtime', () => ({
   ...jest.requireActual('@grafana/runtime'),
   locationService: {
+    getSearchObject: jest.fn().mockResolvedValue({}),
     partial: jest.fn(),
   },
 }));