Fix security, performance, and code quality issues across CMS

Security:
- Replace unescaped {!! !!} with Purify::clean() in 15+ Blade templates (XSS)
- Add rate limiting to register (3/hr), upload (10/min), SSE (6/min)
- Add max:5000 validation on article comments
- Remove duplicate exception handler callback

Hardcoded paths:
- Replace ~44 /var/www/ hardcoded paths with env() configs
- CatalogService (13), AutoDetectService (18), Commandocentrum (11), AppServiceProvider (2)

Performance:
- Add 10 missing database indexes (radio_song_requests, help_center_tickets, etc.)
- Replace Cache::flush() with targeted Cache::forget() in RadioSettings
- Cache getCachedCategories() in TicketController (N+1 fix)
- Remove redundant top-3 leaderboard query

Bug fixes:
- Fix undefined $enabled variable → $isOnline in radio index view
- Add getAvatarAttribute() accessor for non-existent avatar column
- Fix User::guilds() from wrong HasMany to HasManyThrough

Code quality:
- Replace file_get_contents with Http::timeout(10) in TraxService
- Remove commented Echo/Pusher boilerplate in bootstrap.js
- Remove TODO/FIXME comments from logo-generator templates
- Replace hardcoded Turnstile CDN URL with config()
- Restore QUEUE_CONNECTION=redis in .env.example files

app/Http/Controllers/Community/RadioLeaderboardController.php

@@ -23,14 +23,7 @@ class RadioLeaderboardController extends Controller
             default => $this->getAllTimeLeaderboard(),
         };
 
-        // Extract top 3 from already-fetched data
-        $topUserData = array_slice($users, 0, 3);
-        $topUserIds = array_column($topUserData, 'id');
-        $topUsers = User::whereIn('id', $topUserIds)
-            ->get()
-            ->keyBy('id');
-
-        return view('community.radio.leaderboard', ['users' => $users, 'topUsers' => $topUsers, 'period' => $period]);
+        return view('community.radio.leaderboard', ['users' => $users, 'period' => $period]);
     }
 
     private function getAllTimeLeaderboard(): array
@@ -43,7 +36,7 @@ class RadioLeaderboardController extends Controller
                 'rank' => $index + 1,
                 'id' => $user->id,
                 'username' => $user->username,
-                'avatar' => $user->avatar ?? null,
+                'avatar' => $user->avatar,
                 'points' => $user->radio_points,
             ])
             ->toArray();
@@ -79,7 +72,7 @@ class RadioLeaderboardController extends Controller
                 'rank' => $index + 1,
                 'id' => $item->user_id,
                 'username' => $user?->username ?? 'Onbekend',
-                'avatar' => $user?->avatar ?? null,
+                'avatar' => $user?->avatar,
                 'points' => (int) $item->total_points,
             ];
         })->toArray();