Update deps, docs, auth logic; add SixLabors license

- Expanded copilot-instructions.md with project/routing details and ImageSharp license handling
- Upgraded MailKit and MimeKit to v4.17.0
- Added sixlabors.lic for ImageSharp 4.x licensing
- Removed SecretManagementExtensions.cs stub
- Updated OCORE and OCORE_web submodules
- Improved unauthorized access handling in IntranetController
- Removed empty placeholder file

Fuchs/Controllers/IntranetController.cs

@@ -91,8 +91,10 @@ public partial class IntranetController : Microsoft.AspNetCore.Mvc.Controller
         if (!UserIdent.IsAuthenticated && !(new string[] { "login","logout" }).Contains(fn.ToLower()) && !_allowedNonAuth.Contains(fn.ToLower()))
         {
             if (!_allowedGet.Contains(fn.ToLower()) && !_allowedGet.Contains($"{fn.ToLower()}|{id.ToLower()}"))
+            {
                 _logger.LogInformation($"rejected function on do {fn}");
                 return Unauthorized401();
+            }
         }
 
         try