Function project 

pub async fn project<S: StorageEngine>(
    array_state: &Arc<Mutex<ArrayEngineState>>,
    storage: &Arc<S>,
    name: &str,
    attr_indices: &[u32],
) -> Result<QueryResult, LiteError>

Execute ArrayOp::Project for the Lite engine.

Scans all segments and the memtable, projects to the requested attribute indices, and returns every live cell as a row. The attribute order in the response matches attr_indices — not the schema order.