feat(vikon): move API token from .env to integration_credentials

- Rename VICON_TOKEN → VIKON_API_TOKEN in .env and config
- Add ViconApiToken service reading from integration_credentials table
- Update 3 Vicon services to use ViconApiToken instead of config()
- Config/env kept as fallback for clean migration

config/services.php

@@ -46,9 +46,8 @@ return [
     ],
 
     'vicon' => [
-        'token' => env('VICON_TOKEN'),
+        'token' => env('VIKON_API_TOKEN'),
         'api_url' => 'https://db-nica.ru/api/v1',
     ],
 
-
 ];