small fixes

app/Classes/Settings/System.php

@@ -55,7 +55,7 @@ class System
             'show-tos' => 'string',
             'alert-enabled' => 'string',
             'alter-type' => 'string',
-            'alert-message' => 'string',
+            'alert-message' => 'string|nullable',
         ]);
 
         $validator->after(function ($validator) use ($request) {

themes/default/views/admin/settings/tabs/system.blade.php

@@ -336,6 +336,11 @@
                            class="form-control @error('alert-message') is-invalid @enderror">
                         {{ config('SETTINGS::SYSTEM:ALERT_MESSAGE', '') }}
                         </textarea>
+                    @error('alert-message')
+                    <div class="text-danger">
+                        {{ $message }}
+                    </div>
+                    @enderror
                 </div>
 
             </div>