Fix Laravel 5.5 compatibility issues - view helpers, collections, and auth routes

- Replace {{ url() }} with {{ url('/') }} in all blade templates to fix object-to-string conversion errors
- Update TeamStoreModel::selectTeamStoreGroupByCartKey() to use first() instead of get() for Laravel 5.5 Collections
- Fix TeamStoreController to access object properties directly instead of using array syntax [0]
- Update authentication routes to use Laravel 5.5 method names (showLoginForm, login, logout)
- Update login/register links from /auth/login to /login throughout views (navbar, app, auth pages)
- Verify cart, login, and register pages working with HTTP 200 status

app/Http/Controllers/MainController.php

@@ -50,7 +50,7 @@ class MainController extends Controller {
 		$categoryids = array();
 		
 		foreach($data as $row){
-			$categoryids[] =  $row->Category;
+			$categoryids[] =  (string)$row->Category;
 		}
 
 		$array_sports 	 = $m->selectSportsByURL($url);