refactor(web,server): use feature flags for oauth (#3928)

* refactor: oauth to use feature flags

* chore: open api

* chore: e2e test for authorize endpoint

server/src/domain/auth/dto/oauth-config.dto.ts

@@ -1,9 +1,7 @@
-import { ApiProperty } from '@nestjs/swagger';
 import { IsNotEmpty, IsString } from 'class-validator';
 
 export class OAuthConfigDto {
   @IsNotEmpty()
   @IsString()
-  @ApiProperty()
   redirectUri!: string;
 }