-- 144_documents_category_columns.sql
-- Section 1: documents 에 category / ai_suggestion 컬럼 추가 (2/4)
-- plan: luminous-sprouting-hamster.md §1
--
-- ai_suggestion 구조:
--   {
--     proposed_category, proposed_path, proposed_doctype,
--     confidence, source_updated_at, reason
--   }
-- 자동 전이 금지 — /accept-suggestion 승인 시에만 category / user_tags 변경

ALTER TABLE documents
  ADD COLUMN IF NOT EXISTS category       doc_category,
  ADD COLUMN IF NOT EXISTS ai_suggestion  JSONB;
