refactor(server): auth route metadata (#9344)

server/src/controllers/app.controller.ts

@@ -1,6 +1,5 @@
 import { Controller, Get, Header } from '@nestjs/common';
 import { ApiExcludeEndpoint } from '@nestjs/swagger';
-import { PublicRoute } from 'src/middleware/auth.guard';
 import { SystemConfigService } from 'src/services/system-config.service';
 
 @Controller()
@@ -18,7 +17,6 @@ export class AppController {
   }
 
   @ApiExcludeEndpoint()
-  @PublicRoute()
   @Get('custom.css')
   @Header('Content-Type', 'text/css')
   getCustomCss() {