Ticketing: settings tabs are deep-linkable routes (/settings/{tab})

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jh8RnYXrC8E6z79LWs8ggd

src/Http/Controllers/TicketingSettingsController.php

@@ -64,7 +64,7 @@ class TicketingSettingsController extends Controller
         }
     }
 
-    public function index(): Response
+    public function index(?string $tab = null): Response
     {
         $this->requireAgentAccess();
 
@@ -101,6 +101,7 @@ class TicketingSettingsController extends Controller
             : EmailConnection::whereIn('group_id', $myGroupIds)->get();
 
         return Inertia::render('Ticketing/Settings', [
+            'activeTab'        => $tab,
             'groups'           => $groups,
             'agents'           => $agents,
             'priorities'       => $priorities,