Keeps the dashboard sessions from expiring. (#9263)

* Keeps the dashboard sessions from expiring.
Route dashboard ajax calls through Laravel.
Boots minimal cookies and sessions.
Does not fix other pages for now, real fix is to fully port.

* Check Laravel auth for the legacy calls.
Display Laravel errors in the dashboard.
legacy auth checks are mostly extraneous now.

app/Http/Kernel.php

@@ -41,6 +41,11 @@ class Kernel extends HttpKernel
             \Illuminate\Routing\Middleware\SubstituteBindings::class,
         ],
 
+        'minimal' => [
+            \App\Http\Middleware\EncryptCookies::class,
+            \Illuminate\Session\Middleware\StartSession::class,
+        ],
+
         'api' => [
             'bindings',
             'auth:token'