New endpoint for instant search

Part of #798 (closed)

What does this MR do?

Refactors some parts of the instant search in the topbar:

• Uses a DTO for search results in the SearchGateway
• Creates a new endpoint GET /search/all for the instant search in the topbar
• Removes the client-side wrapper code that mapped the legacy results from the Xhr endpoint
• Adds a permissions class for searches
• Makes all affected functions a bit more PHP 7.4 compatible

How confident are you it won't break things if deployed?

Quite sure, seems to work on localhost. The vue front-end already used the new format and doesn't change. The database request and overall behavior shouldn't change as well.

How to test

Steps a reviewer can take to verify that this MR does what it says it does e.g.

1. Checkout branch locally
2. Login as foodsaver
3. Search for a region, store, or another foodsaver in the topbar
4. Click the results and see if they lead to the correct pages

Checklist

• added a test, or explain why one is not needed/possible...
• no unrelated changes
• asked someone for a code review
• joined #foodsharing-beta channel at https://slackin.yunity.org
• added an entry to CHANGELOG.md (description, merge request link, username(s))
• Once your MR has been merged, you are responsible to update the #foodsharing-beta Slack channel about what has been changed here. They will test your work in different browsers, roles or other settings

src/Controller/SearchRestController.php

@@ -92,9 +92,10 @@ class SearchRestController extends AbstractFOSRestController
 
 			$results = $this->searchGateway->searchUserInGroups(
 				$q,
+				false,
 				$regions
 			);
-			$results = array_map(function ($v) { return ['id' => $v['id'], 'value' => $v['name'] . ' ' . $v['nachname'] . ' (' . $v['id'] . ')']; }, $results);
+			$results = array_map(function ($v) { return ['id' => $v->id, 'value' => $v->name . ' (' . $v->id . ')']; }, $results);
 		}
 
 		return $this->handleView($this->view($results, 200));