feat: teams redesign — cards, filter, user autocomplete

- Teams index: cards with animation, search filter
- Team detail: user autocomplete via AJAX (search on type)
- CSS: card grid styles, autocomplete dropdown
- Backend: searchUsers endpoint, filter support

src/Controllers/TeamController.php

@@ -30,14 +30,53 @@ class TeamController
     public function index(): void
     {
         $userId = (int) Session::get('user_id');
-        $teams = $this->teamModel->findByCreator($userId);
+        $search = $_GET['search'] ?? '';
+
+        if ($search !== '') {
+            $teams = $this->teamModel->findByCreator($userId);
+            $teams = array_filter($teams, function ($team) use ($search) {
+                $s = mb_strtolower($search);
+                return mb_strpos(mb_strtolower($team['name'] ?? ''), $s) !== false
+                    || mb_strpos(mb_strtolower($team['description'] ?? ''), $s) !== false;
+            });
+        } else {
+            $teams = $this->teamModel->findByCreator($userId);
+        }
 
         $this->view->display('teams.index', [
             'title' => 'Teams - ServerManager',
             'teams' => $teams,
+            'search' => $search,
         ]);
     }
 
+    public function searchUsers(): void
+    {
+        $q = $_GET['q'] ?? '';
+        if (mb_strlen($q) < 2) {
+            $this->view->json(['users' => []]);
+            return;
+        }
+
+        $userModel = new User();
+        $allUsers = $userModel->getAll(1, 999);
+        $filtered = array_filter($allUsers['data'], function ($u) use ($q) {
+            $s = mb_strtolower($q);
+            return mb_strpos(mb_strtolower($u['username'] ?? ''), $s) !== false
+                || mb_strpos(mb_strtolower($u['email'] ?? ''), $s) !== false;
+        });
+
+        $results = array_map(function ($u) {
+            return [
+                'id' => (int) $u['id'],
+                'username' => $u['username'],
+                'email' => $u['email'],
+            ];
+        }, array_slice(array_values($filtered), 0, 20));
+
+        $this->view->json(['users' => $results]);
+    }
+
     public function create(): void
     {
         $this->view->display('teams.create', [