ver. 0.294: Code review complete — 96/96 classes, 27 fixes across all layers

Full codebase review of autoload/ directory (96 classes, ~1144 methods).
Fixes: null safety (query/find guards), redundant DI bypass, undefined
variables, missing globals, and Imagick WebP mime type bug in Helpers.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

autoload/admin/App.php

@@ -57,6 +57,11 @@ class App
         if ( $result == 1 )
         {
           $user = $users->details( $login );
+          if ( !$user ) {
+            \Shared\Helpers\Helpers::alert( 'Błąd logowania.' );
+            header( 'Location: /admin/' );
+            exit;
+          }
 
           if ( $user['twofa_enabled'] == 1 )
           {
@@ -116,6 +121,12 @@ class App
         }
 
         $user = $users->details( $pending['login'] );
+        if ( !$user ) {
+          \Shared\Helpers\Helpers::delete_session( 'twofa_pending' );
+          \Shared\Helpers\Helpers::alert( 'Sesja wygasła. Zaloguj się ponownie.' );
+          header( 'Location: /admin/' );
+          exit;
+        }
         self::finalize_admin_login( $user, $domain, $cookie_name, !empty( $pending['remember'] ) );
         header( 'Location: /admin/articles/list/' );
         exit;