fix(admin-service): exclude /downloads from API prefix

Downloads route was getting /api/v1 prefix, making it inaccessible at /downloads

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/services/admin-service/src/main.ts

@@ -7,11 +7,12 @@ async function bootstrap() {
   const logger = new Logger('Bootstrap')
   const app = await NestFactory.create(AppModule)
 
-  // Global prefix (exclude mobile API routes that need custom paths)
+  // Global prefix (exclude mobile API routes and downloads that need custom paths)
   app.setGlobalPrefix('api/v1', {
     exclude: [
       { path: 'api/app/version/(.*)', method: RequestMethod.ALL },
       { path: 'api/app/version/check', method: RequestMethod.GET },
+      { path: 'downloads/(.*)', method: RequestMethod.GET },
     ],
   })