GET /items/{item_id}

curl http://localhost:8000/items/item-abc123

{
  "kos_id": "item-abc123",
  "tenant_id": "demo",
  "user_id": "user-1",
  "source": "files",
  "external_id": "doc-456",
  "title": "Introduction to Machine Learning",
  "content_text": "Machine learning is a subset of...",
  "content_type": "article",
  "created_at": "2025-01-15T10:30:00Z",
  "updated_at": "2025-01-15T10:30:00Z",
  "metadata": {},
  "passages": [
    {
      "kos_id": "passage-1",
      "text": "Machine learning is a subset of artificial intelligence...",
      "sequence": 0,
      "metadata": {}
    },
    {
      "kos_id": "passage-2",
      "text": "Key concepts include supervised learning...",
      "sequence": 1,
      "metadata": {}
    }
  ],
  "entities": []
}

POST /items

curl -X POST http://localhost:8000/items \
  -H "Content-Type: application/json" \
  -d '{
    "tenant_id": "demo",
    "user_id": "user-1",
    "source": "files",
    "title": "Introduction to Machine Learning",
    "content_text": "Machine learning is a subset of artificial intelligence that enables systems to learn and improve from experience without being explicitly programmed.",
    "content_type": "article",
    "metadata": {
      "author": "John Doe",
      "category": "technology"
    }
  }'

{
  "kos_id": "item-abc123",
  "tenant_id": "demo",
  "user_id": "user-1",
  "source": "files",
  "external_id": null,
  "title": "Introduction to Machine Learning",
  "content_text": "Machine learning is a subset of...",
  "content_type": "article",
  "created_at": "2025-01-15T10:30:00Z",
  "updated_at": "2025-01-15T10:30:00Z",
  "metadata": {
    "author": "John Doe",
    "category": "technology"
  },
  "passages": [],
  "entities": []
}