'suggest topic title' AI 도우미 사용 시 500 내부 서버 오류 발생

유사한 주제들이 있지만, 이건 새로운 문제인 것 같습니다. 다른 유사 주제들은 모두 해결된 상태로 표시되어 있습니다.

요약: 주제 제목을 제안할 때 500 오류가 발생합니다.
(교정, 마크다운 테이블 생성, 태그 제안, 임베딩, 검색/시맨틱 기능은 모두 정상 작동합니다)
셀프 호스팅 v2026.10.0-latest +401, Digitalocean 드롭렛 및 서버리스 추론, DO 엔드포인트를 통한 Deepseek 3.2 사용 중입니다.

로그에서 다음 오류가 발생합니다:

Failed to process hijacked response correctly : NoMethodError : undefined method 'flatten' for an instance of String
/var/www/discourse/plugins/discourse-ai/lib/ai_helper/assistant.rb:202:in 'DiscourseAi::AiHelper::Assistant#generate_and_send_prompt' 
/var/www/discourse/plugins/discourse-ai/app/controllers/discourse_ai/ai_helper/assistant_controller.rb:65:in 'block in DiscourseAi::AiHelper::AssistantController#suggest_title' 
/var/www/discourse/lib/hijack.rb:68:in 'BasicObject#instance_eval' 
/var/www/discourse/lib/hijack.rb:68:in 'block (2 levels) in Hijack#hijack' 
i18n-1.14.8/lib/i18n.rb:354:in 'I18n::Base#with_locale' 
/var/www/discourse/lib/hijack.rb:68:in 'block in Hijack#hijack' 
concurrent-ruby-1.3.8/lib/concurrent-ruby/concurrent/promises.rb:911:in 'Concurrent::Promises::Event#callback_on_resolution' 
concurrent-ruby-1.3.8/lib/concurrent-ruby/concurrent/promises.rb:797:in 'Concurrent::Promises::AbstractEventFuture#call_callback' 
concurrent-ruby-1.3.8/lib/concurrent-ruby/concurrent/promises.rb:803:in 'Concurrent::Promises::AbstractEventFuture#call_callbacks' 
concurrent-ruby-1.3.8/lib/concurrent-ruby/concurrent/promises.rb:692:in 'Concurrent::Promises::AbstractEventFuture#resolve_with' 
concurrent-ruby-1.3.8/lib/concurrent-ruby/concurrent/promises.rb:1331:in 'Concurrent::Promises::ResolvableEvent#resolve' 
/var/www/discourse/lib/scheduler/defer.rb:135:in 'block in Scheduler::Deferrable#do_work' 
rails_multisite-9.0.0/lib/rails_multisite/connection_management/null_instance.rb:54:in 'RailsMultisite::ConnectionManagement::NullInstance#with_connection'
rails_multisite-9.0.0/lib/rails_multisite/connection_management.rb:23:in 'RailsMultisite::ConnectionManagement.with_connection'
/var/www/discourse/lib/scheduler/defer.rb:130:in 'Scheduler::Deferrable#do_work' 
/var/www/discourse/lib/scheduler/defer.rb:116:in 'block (2 levels) in Scheduler::Deferrable#start_thread' 

추가로 제공할 수 있는 정보가 있다면 알려주세요.