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/Auth/AuthController.php

@@ -1,40 +1,32 @@
 <?php namespace App\Http\Controllers\Auth;
 
 use App\Http\Controllers\Controller;
-use Illuminate\Contracts\Auth\Guard;
-use Illuminate\Contracts\Auth\Registrar;
-use Illuminate\Foundation\Auth\AuthenticatesAndRegistersUsers;
+use Illuminate\Foundation\Auth\AuthenticatesUsers;
 
 class AuthController extends Controller {
 
 	/*
 	|--------------------------------------------------------------------------
-	| Registration & Login Controller
+	| Login Controller
 	|--------------------------------------------------------------------------
 	|
-	| This controller handles the registration of new users, as well as the
-	| authentication of existing users. By default, this controller uses
-	| a simple trait to add these behaviors. Why don't you explore it?
+	| This controller handles authenticating users for the application.
 	|
 	*/
 
-	use AuthenticatesAndRegistersUsers;
+	use AuthenticatesUsers;
+	
 	protected $redirectTo = '/';
 
 	/**
 	 * Create a new authentication controller instance.
 	 *
-	 * @param  \Illuminate\Contracts\Auth\Guard  $auth
-	 * @param  \Illuminate\Contracts\Auth\Registrar  $registrar
 	 * @return void
 	 */
 	
-	public function __construct(Guard $auth, Registrar $registrar)
+	public function __construct()
 	{
-		$this->auth = $auth;
-		$this->registrar = $registrar;
-
-		$this->middleware('guest', ['except' => 'getLogout']);
+		$this->middleware('guest')->except('logout');
 	}
 
 }