Large Dataset Demo API
      
      Available endpoints:
      - /insert?count=100000 : Insert records (default 100)
      - /read         : Read all records (streams response)
      - /read?limit=1000 : Read limited records
      - /read?compact=true : Compact output (better performance)
      - /count        : Count records
      - /clear        : Delete all records
      - /query/stream : Stream SQL queries (requires Authorization header)
      
      SQL Streaming API:
      POST /query/stream
      Headers: Authorization: Bearer your-api-key (or just: your-api-key)
      Body: { "query": "SELECT * FROM large_users LIMIT 10", "bindings": [] }
      
      Example curl:
      curl -X POST https://your-worker.domain.com/query/stream \
        -H "Authorization: demo-key-123" \
        -H "Content-Type: application/json" \
        -d '{"query": "SELECT id, name FROM large_users LIMIT 5"}'